source string | id string | question string | options list | answer string | reasoning string |
|---|---|---|---|---|---|
OpenBookQA | OpenBookQA-4501 | species-identification, botany
Title: Can you identify this (possibly waterstoring) plant? My son brought home a sapling, and after 4 years in a pot it is now about 30 cm or a foot high (from the "ground" to the top of the "stem"). It doesn't need a lot of water and can go weeks without being watered, in fact it seems to me as if it is storing water in the thicker upper part of its stem. When I water it "too much", new leaves start to grow. There are tiny "blossoms" along the stem, and every now and then small, dark brown, spherical seeds about 2 mm in diameter pop out from the "blossom" and are thrown across the room as far as a meter (about a yard) or two.
What plant is this?
I believe that it is not native to my European home but some kind of decorative plant imported and sold through a florist or imported privately, but I'm not sure. It is an Euphorbia leuconeura (Madagascar Jewel), which is native to Madagaskar. The leaves and the thick (waterstoring) stem with a narrow base is very typical.
The plant is cool in the sense that it easily produces seeds (also as potted) which it can shoot away from the plant. I've had it myself and you can sometimes hear seeds hitting the window or floor. Even if it is easy to grow and to reproduce it is actually considered threatened in its native habitat (IUCN Red-listed as Vulnerable) due to habitat loss
The flowers are very small and found directly on the stem, see below:
(picture from Wikipedia)
The following is multiple choice question (with options) to answer.
A willow can make its own | [
"rain",
"energy",
"sunshine",
"snow"
] | B | a producer produces its own food |
OpenBookQA | OpenBookQA-4502 | bond
Title: Is energy required to form bonds [phase change] My question is if any energy is required to form bonds, for instance when there is a phase change?
If I am correct, energy might be required in the beginning, to make the reaction start and then release a bigger amount of energy than it was putted in. However, in terms of molecular behaviour in a phase change, I think there should not be any energy required to make the molecules to form bonds, if they are placed in a system which has a lower temperature than the molecules. Would they not lose the kinetic energy after a specific time? Bond formation always lowers the energy of the system (or bond formation is a consequence of lower energy, take your pick.)
Indeed, you may have to add energy, because presumably certain bonds must break in order to rearrange the atoms.
Adding energy won't guarantee formation of much higher energy isomers, because the atoms have a large amount of kinetic energy, and so they can just as easily turn around and go back whence they came.
Sometimes the kinetic energy can be dissipated by solvent, collisions with inert gasses, etc. and then you may end up with a measurable quantity of the higher energy species.
The following is multiple choice question (with options) to answer.
What requires energy for growth? | [
"a car",
"a hippopotamus",
"a house",
"a desk"
] | B | an organism requires energy for growth |
OpenBookQA | OpenBookQA-4503 | astronomy, everyday-life, popular-science, climate-science
It is for much the same reason that Winter is colder than Autumn, even though they have the same amount of daylight hours.
The following is multiple choice question (with options) to answer.
At a specific point in a frigid month, the waking hours illumination will be | [
"ending sooner",
"overwhelming hot",
"lasting the longest",
"growing new plants"
] | A | the amount of daylight is least on the winter solstice |
OpenBookQA | OpenBookQA-4504 | human-biology, food, neurotransmitter, receptor, taste
Title: Why do Hot/Cold drinks taste sweeter once returning to room temperature? Now, I know this is a very bizarre question, and I tried to find a correct exchange for this, but it might relate to biology/science as it being our taste buds and everything.
I am so sorry if there is a better exchange for this, but (I hate using this excuse) I'm new to StackExchange, so please be gentle and point me in the right direction.
Now, to meat and bones (Unintended pun; meat...bones...biology hehe), over the last few days I have noticed that after my drink returning to room temperature, it is so much sweeter than it originally tasted.
Drinks
Hot Tea - I normally only add 1-2 teaspoons of sugar into my tea and it tastes just right, though after taking a sip when it had returned to room temperature, it tastes about 3 or 4 times sweeter than when it was hot/warm. (Milk)
Iced Tea (Bubble Tea) - Just today I had a bubble tea with the smallest amount of sugar possible, it was still too sweet but I stuck with it, and again when it reached room temperature, it was almost unbearably sweet. (No milk)
Slurpee - Again, after returning to room temperature, it is extremely sweet, with it being much lighter with respect to sweetness.
Hot Coffee - Come to think of it, I have also had the same experience with sugared coffee.
Coke - Also, when coke (or any other soft drink) is flat and room temperature, it also produces the same super sweet taste.
The following is multiple choice question (with options) to answer.
What stimulants taste buds sour and | [
"sand",
"lava",
"sucrose",
"water"
] | C | sugar causes food to taste sweet |
OpenBookQA | OpenBookQA-4505 | carbohydrates, hydrolysis, taste
Title: Why are polysaccharides not sweet in taste? Polysaccharides are defined as polyhydroxy aldehyde or ketone which on hydrolysis yield many units of monosaccharides.
I got one answer(to my question above) as:
On our tongue, we have things called taste receptors. These receptors are loosely categorised into sweet, sour, bitter and salty. Our sweet-receptors bind to specific types of molecules, namely monosaccharides and disaccharides. Polysaccharides are not as sweet because they do not readily bind to the sweet-receptors on our tongue, as the other smaller molecules do!
My question is that in our body (due to the presence of water),polysaccharides and oligosaccharides are hydrolysed to simpler units of monosaccarides...
So why does the latter respond to the receptors(indicating sweetness) while the former does not(while both yield monosaccarides on hydrolysis)? Well, while indeed polysacharides are metabolised to simpler units, even in mouth (saliva in the mouth can account for 30% of initial starch digestion), it usually doesn't happen fast enough, so full digestion follows later in you digestive system.
You can`t sense the sweetness of polysaccharides as they do not fit the receptors.
The following is multiple choice question (with options) to answer.
Which likely would taste most similarly to sugar? | [
"tobacco",
"meat",
"a tangerine",
"rice"
] | C | sugar causes food to taste sweet |
OpenBookQA | OpenBookQA-4506 | newtonian-mechanics, orbital-motion, free-body-diagram
Push it a bit sideways while letting go and it still crashes but a bit more to the side.
Push it even more, and it still crashes but this time far to the side.
Now push so hard that it reaches such a great sideways speed that although it still falls, it misses! It misses Earth entirely! It falls past Earth and is now flying away from earth on the other side. Earth's gravity slows it down until it eventually comes back again - and it will due to symmetry miss again, this time from the other side. It will repeat this forever. Your baseball is now tracing out an elliptic orbit.
Give it an even greater sideways speed, and the ellipsis widens. At some specific speed, the ellipsis becomes just as wide as it is tall - you now have circular orbit. The distance to the ground is now constant, the same at any moment.
Adjust your altitude, and you will be able to find a place where the sideways speed necessary for circular orbits perfectly matches the sideways speed of Earth's surface due to its rotation. Meaning, a place where the orbital period is 24 hours. Then you have what is called a geosynchronous orbit.
This might be the most peculiar of all orbits, because now your ball looks stationary when we look at it from the ground. It looks as though it is just hanging there in an invisible thread, just floating weightlessly. This is typically the positioning of satellites that must cover the globe in precise and sowewhat fixed patterns.
But in reality it is still falling. Every satellite and space station and astronaut and baseball in geosynchronous orbit, is still falling. Your rotational speed while standing on Earth's surface just happens to match this motion, so that the relative speed* seems to be zero. Only an object in deep outer space away from any gravitational field can truly be called weightless. Anywhere else it would be constantly falling.
Whenever you see astronauts in orbit free-floating, then they are actually not stationary. They just move (fall) at exactly the same speed* as the cameraman.
The following is multiple choice question (with options) to answer.
What drifts above the earth longer? | [
"an iron throne",
"a rock",
"a fat crowd-worker",
"an inflatable toy"
] | D | a beach ball contains gas |
OpenBookQA | OpenBookQA-4507 | java, game, 2048
boolean addNewCell(){
int amountOfEmptyCells = getAmountOfEmptyCells();
int numOfCellToFill;
int counterOfEmptyCells = 0;
if(amountOfEmptyCells == 0) {
return false;
}
numOfCellToFill = Math.abs(new Random().nextInt()%amountOfEmptyCells)+1;
out:
for(int y = 0; y < area.length; y++) {
for(int x = 0; x < area[0].length; x++) {
if(area[y][x].isEmpty()) {
counterOfEmptyCells++;
if(counterOfEmptyCells == numOfCellToFill) {
area[y][x].setBeginNumber();
break out;
}
}
}
}
return true;
}
The following is multiple choice question (with options) to answer.
In order to play with a beach ball, you need to fill it with | [
"with ice",
"with water",
"a gaseous substance",
"with oil"
] | C | a beach ball contains gas |
OpenBookQA | OpenBookQA-4508 | ecology, population-dynamics, ecosystem, antipredator-adaptation, predation
I would also like to talk about other things that might be of interest in your model (two of them need you to allow evolutionary processes in your model):
1) lineage selection: predators that eat too much end up disappearing because they caused their preys to get extinct. This hypothesis has nothing to do with some kind of auto-regulation for the good of species. Of course you'd need several species of predators and preys in your model. This kind of hypothesis are usually considered as very unlikely to have any explanatory power.
2) Life-dinner principle. While the wolf runs for its dinner, the rabbit runs for its life. Therefore, there is higher selection pressure on the rabbits which yield the rabbits to run in average slightly faster than wolves. This evolutionary process protects the rabbits from extinction.
3) You may consider..
more than one species of preys or predators
environmental heterogeneity
partial overlapping of distribution ranges between predators and preys
When one species is absent, the model behave just like an exponential model. You might want to make a model of logistic growth for each species by including $K_x$ and $K_y$ the carrying capacity for each species.
Adding a predator (or parasite) to the predator species of interest
... and you might get very different results.
The following is multiple choice question (with options) to answer.
All predators are also carnivorous because predators | [
"listen to music",
"make stuff",
"cook veggies",
"ingest flesh"
] | D | some birds are predators |
OpenBookQA | OpenBookQA-4509 | One important takeaway here is that we're not thinking of "implies" in terms of causality or possibility. If you want to talk about such things, we have to go beyond propositional logic - modal logic is a good place to set up shop.
Any if-then statement beginning with "If" and then something that has a value of False (not P in this case) is what's called "vacuously true". In some sense, it doesn't matter whether or not the implication would have held if that false statement after the if were true, because it isn't.
Your reasoning is fine ... but it's just that within the context of logic, any kind of 'if .. then ..' statement is analyzed using the mathematically defined material conditional ... and that can lead to some unexpected results since thate material conditional does not always quite match the English conditional.
So, you didn't "screw up" ... in fact, you were right to question this very result, but there are also excellent reasons for analyzing 'if .. then..' using the material conditional, so you better get used to the material conditional in the context of logic.
If you want to know more about this very issue, I suggest you look up "paradoxes of material implication"
You need to go back to the definition of the implication :
$$\begin{matrix} P & Q & P \Rightarrow Q \\ true & true & true\\ true & false & false\\ false & true & true\\ false & false & true \\ \end{matrix}$$
Now let's adapt it to the proposition ' If (not P) then (not Q)', i.e. $not(P) \Rightarrow not(Q)$:
$$\begin{matrix} P & Q & not(P) & not(Q) & not(P) \Rightarrow not(Q) \\ true & true & false & false & true\\ true & false & false & true & true\\ false & true & true & false & false\\ false & false & true & true & true\\ \end{matrix}$$
The following is multiple choice question (with options) to answer.
Which relationship is likely true? | [
"sharks eat seaweed",
"cats eat grass",
"dogs eat light",
"ospreys eat perch"
] | D | some birds are predators |
OpenBookQA | OpenBookQA-4510 | food, biotechnology
Title: How to increase the shelf life of yogurt without refrigeration? When we make yogurt at home and do not refrigerate it, it will become sour because of conversion of lactose into lactic acid by Lactobacillus bacteria, but this does not happen in case of Nestle's yogurt or any other brand until it remains air tight.
I wonder though bacteria is still present in it and continue to convert lactose into lactic acid then why does not packed yogurt becomes sour? How these companies increase the shelf life of yogurt..? This article gives an excellent review on yogurt manufacturing, but to summarize:
-Raw milk goes through centrifugation to remove somatic cells and other solid impurities.
-Thermalization is conducted at "60–69 °C for 20–30 s, aiming at the killing of many vegetative microorganisms and the partial inactivation of some enzymes."
After this point, the milk may be inoculated with lactic acid bacteria or other microfloras.
-Then, standardization occurs which for milk refers to the standardization of fat and solid-non-fat content (SNF). This in short affects the fermentation process ("an increase of SNF increases the duration of the fermentation process").
-The next step is homogenization, which prevents milk fat from rising to the top of the liquid. This has an effect on the stability of the emulsion.
-I think this step is where "sterility" comes into play, "heat treatment of milk reduces the number of pathogenic microorganisms to safe limits for the consumer’s health. Various heat treatments can be applied, which are classified based on the duration and the temperature. The most common are known as thermalization, low and high pasteurization, sterilization and UHT (Ultra Heat Treatment)." The review goes into more detail about each type and what they eliminate or don't eliminate (spores, vegetative bacteria, etc.).
The following is multiple choice question (with options) to answer.
Milk sold in supermarkets is pasteurized because | [
"all raw milk is safe",
"to keep bacteria from getting into the milk after the customer buys it",
"the factory farmed cows produce a lot of pus in their milk",
"that makes it taste better"
] | B | Louis Pasteur invented pasteurization |
OpenBookQA | OpenBookQA-4511 | physiology, neurophysiology, respiration, breathing, pulmonology
Title: Is breathing a reflex action or is it an intrinsic process? The process of breathing is controlled by respiratory centers in the brain stem. Do these centers have an innate activity, i.e., just send out signals to breathing muscles intrinsically, and have the rate and manner in which they do so modified by various regulatory factors?
Or are they driven by imbalances (in levels of oxygen, carbon dioxide, hydrogen ions) like a reflex? Let's say that hypothetically these levels remain static in an acceptable state such that this reflex is no longer needed, would breathing stop since there's no longer a driving motive or would it continue because the respiratory centers have an intrinsic activity? While the ultimate purpose of breathing could be considered to be the maintainance of a balance of the substances you are referring to (such as blood oxygen, carbon dioxide, and hydrogen ions), the blood levels of these substances do not directly control the production of action potentials within the motor neurons that promote the contraction of the diaphragm and intercostal muscles.
The propagation of these action potentials is initiated by signals from the medullary respiratory center, specifically the neurons in the dorsal respiratory group (DRG) and the ventral respiratory group (VRG). In the VRG, a complex of neurons known pre-Bötzinger complex is responsible for generating the signals that cause the rhythmic muscle contractions involved in breathing:
The respiratory rhythm generator is located in the pre-Bötzinger complex of neurons in the upper part of the VRG. This rhythm generator appears to be composed of pacemaker cells and a complex neural network that, acting together, set the basal respiratory rate.
The following is multiple choice question (with options) to answer.
Which of the following breathes? | [
"a basketball",
"a rope",
"a saw",
"a zebra"
] | D | all animals breathe |
OpenBookQA | OpenBookQA-4512 | ros-kinetic
Abandoned <<< play_motion [ Unrelated job failed ]
Abandoned <<< tiago_2dnav_gazebo [ Unrelated job failed ]
Abandoned <<< tiago_bringup [ Unrelated job failed ]
Abandoned <<< tiago_controller_configuration_gazebo [ Unrelated job failed ]
Abandoned <<< tiago_description [ Unrelated job failed ]
Abandoned <<< tiago_gazebo [ Unrelated job failed ]
Abandoned <<< tiago_multi [ Unrelated job failed ]
Abandoned <<< pal_hardware_gazebo [ Unrelated job failed ]
The following is multiple choice question (with options) to answer.
After the Meyer tree's flowers pedals drop you are left with | [
"a bee sign",
"something sweet",
"a bird bath",
"a party"
] | B | some flowers become fruits |
OpenBookQA | OpenBookQA-4513 | ## A number of people shared a meal, intending to divide the cost evenly among themselves. However, several of the diners
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### A number of people shared a meal, intending to divide the cost evenly among themselves. However, several of the diners
by Vincen » Sat Nov 27, 2021 4:38 am
00:00
A
B
C
D
E
## Global Stats
A number of people shared a meal, intending to divide the cost evenly among themselves. However, several of the diners left without paying. When the cost was divided evenly among the remaining diners, each remaining person paid $$\12$$ more than he or she would have if all diners had contributed equally. Was the total cost of the meal, in dollars, an integer?
(1) Four people left without paying.
(2) Ten people in total shared the meal.
Source: Veritas Prep
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### Re: A number of people shared a meal, intending to divide the cost evenly among themselves. However, several of the dine
by [email protected] » Sat Nov 27, 2021 7:31 am
00:00
A
B
C
D
E
## Global Stats
Vincen wrote:
Sat Nov 27, 2021 4:38 am
A number of people shared a meal, intending to divide the cost evenly among themselves. However, several of the diners left without paying. When the cost was divided evenly among the remaining diners, each remaining person paid $$\12$$ more than he or she would have if all diners had contributed equally. Was the total cost of the meal, in dollars, an integer?
(1) Four people left without paying.
(2) Ten people in total shared the meal.
Source: Veritas Prep
Target question: Was the total cost of the meal, in dollars, an integer?
This is a great candidate for rephrasing the target question
The following is multiple choice question (with options) to answer.
Because lack of sustenance 1 out of 4 people are | [
"chronically craving",
"fairies",
"unicorns",
"wizards"
] | A | lack of food causes starvation |
OpenBookQA | OpenBookQA-4514 | ecology, population-dynamics, ecosystem, antipredator-adaptation, predation
I would also like to talk about other things that might be of interest in your model (two of them need you to allow evolutionary processes in your model):
1) lineage selection: predators that eat too much end up disappearing because they caused their preys to get extinct. This hypothesis has nothing to do with some kind of auto-regulation for the good of species. Of course you'd need several species of predators and preys in your model. This kind of hypothesis are usually considered as very unlikely to have any explanatory power.
2) Life-dinner principle. While the wolf runs for its dinner, the rabbit runs for its life. Therefore, there is higher selection pressure on the rabbits which yield the rabbits to run in average slightly faster than wolves. This evolutionary process protects the rabbits from extinction.
3) You may consider..
more than one species of preys or predators
environmental heterogeneity
partial overlapping of distribution ranges between predators and preys
When one species is absent, the model behave just like an exponential model. You might want to make a model of logistic growth for each species by including $K_x$ and $K_y$ the carrying capacity for each species.
Adding a predator (or parasite) to the predator species of interest
... and you might get very different results.
The following is multiple choice question (with options) to answer.
A lone fox is searching for its next meal in a meadow that used to be bountiful with food. This season, though, rabbits have all been eaten up and the field is dry and barren. The fox may | [
"fly",
"say something",
"hibernate",
"starve"
] | D | lack of food causes starvation |
OpenBookQA | OpenBookQA-4515 | ocean, oceanography, sea-level, tides
However, I'm really curious as which are the most important amongst them? Or is it even possible to guess the tide height if I know the Lunar phase and I have a good globe with sea depth? I don't know about the size of land masses, but their distribution and the shape of ocean basins definitely play a big role.
When considering the ideal case of an all-ocean globe, i.e. one with no land masses (equilibrium tidal theory), the combined effect of sun and moon give a theoretical tidal range of less than 1 m(1). As tidal ranges can be much larger than this, there are other effects that has a greater influence.
The Bay of Fundy for example, is one of the places with the largest difference between low tide and high tide, at about 16 m. The large difference in this location has to do with the shape of the bay. The bay has a natural frequency for waves that is about the same as the frequency of the tide itself, giving an amplification of the tidal amplitude. In addition there is a funnelling effect in the inner part of the bay, giving an additional contribution.(2)
Another example of large tidal differences is the English channel, particularly the French side. In this case the tides are large at least partly because the tide moves as a coastal trapped Kelvin wave. These are waves that propagate along land, with the land to the right when looking in the direction of propagation (on the Northern hemisphere, land to the right on SH). The amplitude of the wave is highest near the coast, decaying exponentially away from the coast. As the tide in the English channel moves northward, the largest tidal range is on the French side.
With regard to guessing the tidal range, this is not entirely straight forward.
First, when discussing tides, we generally split the tidal potential into a series of oscillations having different frequencies, mainly either diurnal (period of ~24 h) or semi-diurnal (period of ~12 h).
These given frequencies are obtained through trigonometric considerations, and depend on the latitude of the point, the declination of the moon or sun relative to the equator, and the hour angle.
(The hour angle is basically the longitudinal difference between the sub-lunar point and the point we consider.)
Each of these components can vary in time and space.
The following is multiple choice question (with options) to answer.
Which would likely most impact a barometer? | [
"gale-force winds",
"thunder",
"light breezes",
"lightning"
] | A | as air pressure increases , the reading on a barometer will rise |
OpenBookQA | OpenBookQA-4516 | ocean, ocean-currents, tides
Physical effects, then, are likely to include direct effects on current speed, sediment, and stratification.
The obvious possible biological effect is from collisions. This is not my field, but as I understand it no effect is likely on small fish populations from collisions, although individuals may be affected. Collision risk for large animals (e.g. sharks and marine mammals) and for diving birds is a topic of active research, and is likely (especially for mammals) to depend on their behaviour around the devices. No large animal collisions have been reported on any of the prototypes undergoing testing so far.
A good review of possible effects on benthic organisms is provided by Shields et al (2011). These may include,
The following is multiple choice question (with options) to answer.
Which likely has a negative impact? | [
"water on the glaicial environment",
"life on the glaicial environment",
"cold on the glaicial environment",
"heat on the glaicial environment"
] | D | glaciers melting has a negative impact on the glaicial environment |
OpenBookQA | OpenBookQA-4517 | inorganic-chemistry, home-experiment
Title: Make a silver zinc battery I have a shaver that runs off a rechargeable battery that is dying. Would it be feasible to make a silver zinc battery and use it to replace the existing battery? Cost is not an object, anything less than $2500 I would consider doable. I have a machine shop and a small chemistry laboratory with the standard equipment and glassware, including high vacuum capability, a centrifuge and simple glass blowing capability.
I found a book on silver-oxide zinc chemistry and battery design, but it is $500 and I don't want to spend that if the information can be obtained just as easily elsewhere.
I have tried to find commercial options, but had no luck. Most silver zinc batteries seem to be just for large (multi-million dollar) military or satellite applications. Sony makes a line of silver oxide primary cells for hearing aids, but these are not rechargeable. There is a company called Ultralife that makes medical and military batteries and might have something viable, but before I call them I wanted to check out the opinion of the experts here. This turns out to be very difficult to do for two reasons. One problem is that the voltage of a silver cell is different from that of Ni-Cd cell, so it would require a specialized, multi-cell configuration to emulate the voltage characteristics of the Ni-Cd rechargeables.
The other problem is that silver cells generally have a sophisticated frame inside of them that is produced by an intricate high-temperature welding process. To duplicate this process and produce a suitable frame would require a significant amount of experimentation and work.
The following is multiple choice question (with options) to answer.
Flashlights require batteries | [
"to make light bright rooms darker",
"to meet weight requirements",
"to be used as a weapon",
"to properly illuminate objects"
] | D | a battery converts chemical energy into electrical energy |
OpenBookQA | OpenBookQA-4518 | thermodynamics, energy, electricity, efficient-energy-use
Title: Cutting down on power by bypassing mechanical to electrical conversions: Why not? The only answer to this I can think of is energy portability issues.
Another modern-world insanity is converting mechanical energy to electrical, only to turn it back into mechanical. The example I like to use is a refrigerator's reciprocating compressor.
If we directly attach a steam turbine's axle to the crankshaft of the compressor, we will not need to suffer losses in heat in our conversion of mechanical to electrical (at the power plant) then back to mechanical energy (in our appliance). Long ago, a primitive factory used one big engine or turbine or water wheel to rotate a set of overhead shafts, from which leather belts were suspended at intervals to power small pieces of machinery scattered throughout the factory. This arrangement was inflexible in that when the single big engine stopped, so did the entire factory, and when electricity came into common use, this overhead shafting arrangement fell quickly out of favor.
The power losses in long-distance electrical power transmission are more than made up for by the ease with which it is performed and the flexibility it affords. This makes "local power generation" as you describe it impractical because a hundred small steam turbines are much more wasteful of heat energy than one large turbine.
The only practical exception is integrated co-generation in which a small engine running on, for example, natural gas powers a generator while also spinning the shaft of a heat pump. The waste heat from the engine's cooling system makes residential hot water, the waste heat from its exhaust goes through a heat exchanger to provide hot air for space heating, the heat pump furnishes air conditioning (or pulls heat from outside the dwelling) and the electricity from the generator powers up your small appliances in the home while also charging a set of batteries.
Overall thermodynamic efficiency of such a device can exceed 95%, and examples of this technology are just now coming onto the market.
The following is multiple choice question (with options) to answer.
People are switching from coal to wind to | [
"do nothing at all",
"heat and cool Mars",
"sing songs to birds",
"producing heat for dwellings"
] | D | wind is used for producing electricity |
OpenBookQA | OpenBookQA-4519 | zoology, ornithology, ethology, behaviour
Title: Crow branch pecking behaviour I was walking through a small park when two crows started cawing at me, and followed me, flying from tree-to-tree as I walked. I speculate that this is a territorial or protective behaviour, but what I found different was the crows were violently pecking the branches nearby them. I have no memories coming to mind of seeing this behaviour beforehand. I speculate that this behaviour could be threat displays, but a quick search on Google did not reveal to me any authoritative studies on this phenomenon. I'd appreciate more information and sources.
This question has been added as a casual observation on iNaturalist. This is a good question. This type of behavior -- pecking at a branch, wiping the side of the beak on a branch, pulling off twigs and dropping them, or knocking off pieces of bark -- is quite common among many corvid species, particularly when they are interrupted by something or someone that they might consider a threat. This includes not only potential predators but also potentially hostile conspecifics.
It is typically considered to be a form of displacement behavior. The concept of displacement behavior, from classical ethology, posits that when an animal experiences two conflicting drives to do two different things, it doesn't know which to do and does a third thing instead to dissipate the drive or anxiety. For branch-pecking in crows, see E.g Kilham and Waltermire 1990 Ch. 12.
Referece: Kilham, L., & Waltermire, J. (1990). The American crow and the common raven. Texas A&M University Press.
The following is multiple choice question (with options) to answer.
A cardinal makes brief contact with a picnic table, and between them there is | [
"death",
"transactions",
"animosity",
"abrasion"
] | D | friction occurs when two object 's surfaces move against each other |
OpenBookQA | OpenBookQA-4520 | forces, friction
Second picture: larger effective area of contact or in other words higher number of contact points between the protuberances, also as pointed out by Jim.
To conclude, we now can tell that for large macroscopic contact areas, the number of protuberances in contact is larger but since the normal force is distributed over all of them, their deformations are less important (smaller effective microscopic area), whereas the opposite will hold for smaller macroscopic surfaces, where the deformations are very strong and maximize the contact between the junctions, but their numbers is comparatively lower. All of which explains why macroscopic areas don't matter.
As for larger normal forces, it will increase the deformation of junctions and make the coupling between the surfaces stronger.
The following is multiple choice question (with options) to answer.
There is more friction the more rough a surface being touched has, so the most friction would be found in | [
"river stones smashing",
"hands clapping",
"mirrors pressing together",
"stone falling"
] | A | friction occurs when two object 's surfaces move against each other |
OpenBookQA | OpenBookQA-4521 | experimental-chemistry
Pouring the copper sulfate solution into the beaker resulted in a vigorous reaction and quite a bit of heat. I stirred the reaction mixture and let it go to completion. The magnet still stuck strongly to the bottom of the beaker, indicating that there was still substantial powdered iron remaining.
The mixture was decanted to another beaker, with some mostly useless filtering (no good filter paper at hand), and allowed to settle for about an hour. The copper particles produced in the reaction are very small and settle out very slowly. Some of the supernatant solution was transferred to a sample cell, illuminated from the left via an LED flashlight and photographed. This is shown in the next figure:
Despite the light scattering, the green color of the ferrous sulfate solution is evident. The photo will be updated after more particulate has settled out.
The following is multiple choice question (with options) to answer.
You find iron in | [
"pure water",
"helium",
"our planet's crust",
"a cloud"
] | C | the crust is a layer of the Earth |
OpenBookQA | OpenBookQA-4522 | thermodynamics, evaporation, gas, liquid-state
On the water surface, knowing the temperature, we can estimate the vapor pressure and vapor mixture fraction. Then there will be an diffusion process for the water vapor to move out and for the ambient air to move in. Because the water surface doesn't allow the air to further move, a circulation forms. When the water vapor moves out, the water vapor pressure drops, so more liquid water evaporates to fill up the loss of water vapor. The evaporation associates latent heat so water surface area temperature drops (you may see dew on the bowl wall). Then a heat transfer process starts which may initiate water circulation as well.
As this is complex, doing test might be a quick way to get the K value if you assume it is a constant, which is questionable.
The following is multiple choice question (with options) to answer.
Which evaporates from its container when used? | [
"spray deodorant",
"pretzels",
"water",
"dog food"
] | A | when a gas in an open container evaporates, that gas spreads out into the air |
OpenBookQA | OpenBookQA-4523 | zoology, invertebrates, sensory-systems
Regarding the ethics of your "investigation", I'd recommend to just not do it.
Sources:
https://de.wikipedia.org/wiki/Blindschnecke
http://www.animalbase.uni-goettingen.de/zooweb/servlet/AnimalBase/home/species?id=1286
https://en.wikipedia.org/wiki/Cecilioides
http://www.molluscs.at/gastropoda/index.html?/gastropoda/morphology/eyes.html
The following is multiple choice question (with options) to answer.
A person is looking at an organism naked to the human eye. Desiring to observe it more clearly, a person engages the use of | [
"binoculars",
"a telescope",
"a meter stick",
"lab equipment"
] | D | microscope is used to see small things by making them appear bigger |
OpenBookQA | OpenBookQA-4524 | evolution, mycology
Title: Why are some fungi poisonous? There are many poisonous fungi in nature. For example Amanita Phalloides.
What reasons could a fungus need poison for? Some species, like venomous snakes, use poison to kill other species as prey. But what about fungi? I can't think of any purpose for poison in fungi. If poison has no real function in fungi shouldn't evolution get rid of it? The same reason some plants are poisonous: to stop animals from eating them.
The visible part of the fungus is called, rather misleadingly, the fruiting body. It exists to produce and spread spores and thus produce the next fungal generation. Getting eaten, rather obviously, inhibits its ability to do this. Being poisonous discourages animals from eating the fruiting body and thus permits it to complete its life cycle.
The following is multiple choice question (with options) to answer.
In the food chain process fungi have the role of what? | [
"putrefiers",
"builders",
"creators",
"consumers"
] | A | In the food chain process fungi have the role of decomposer |
OpenBookQA | OpenBookQA-4525 | zoology, ornithology, ethology, behaviour
Title: Crow branch pecking behaviour I was walking through a small park when two crows started cawing at me, and followed me, flying from tree-to-tree as I walked. I speculate that this is a territorial or protective behaviour, but what I found different was the crows were violently pecking the branches nearby them. I have no memories coming to mind of seeing this behaviour beforehand. I speculate that this behaviour could be threat displays, but a quick search on Google did not reveal to me any authoritative studies on this phenomenon. I'd appreciate more information and sources.
This question has been added as a casual observation on iNaturalist. This is a good question. This type of behavior -- pecking at a branch, wiping the side of the beak on a branch, pulling off twigs and dropping them, or knocking off pieces of bark -- is quite common among many corvid species, particularly when they are interrupted by something or someone that they might consider a threat. This includes not only potential predators but also potentially hostile conspecifics.
It is typically considered to be a form of displacement behavior. The concept of displacement behavior, from classical ethology, posits that when an animal experiences two conflicting drives to do two different things, it doesn't know which to do and does a third thing instead to dissipate the drive or anxiety. For branch-pecking in crows, see E.g Kilham and Waltermire 1990 Ch. 12.
Referece: Kilham, L., & Waltermire, J. (1990). The American crow and the common raven. Texas A&M University Press.
The following is multiple choice question (with options) to answer.
An example of an instinctive behavior is a baby bird pecking at its shell to what? | [
"emerge",
"hide",
"eat",
"remain"
] | A | An example of an instinctive behavior is a baby bird pecking at its shell to hatch |
OpenBookQA | OpenBookQA-4526 | zoology, ethology, behaviour, psychology, death
I can't prove it to you, but I know that my Beagle had a rich emotional life. I know this because I spent huge amounts of time with him. He was a close friend of mine. I would just as soon question whether my wife has real emotions as my dog. I can't prove that my wife's emotions are real either, but I don't have to. It would be silly to assume that everything she shares with me is some sort of evolutionary programming, and not real emotion. Now, when I extend this to cetaceans, I must admit that I don't have any friends in those circles. So I can only guess.
The following is multiple choice question (with options) to answer.
A creature exhibiting an instinctive behavior may | [
"use rocks to open shells",
"climb trees to reach fruit",
"use tools to paint houses",
"make trades with other creatures"
] | B | An example of an instinctive behavior is a baby bird pecking at its shell to hatch |
OpenBookQA | OpenBookQA-4527 | geology, fossil-fuel, petroleum
For some transport applications, the energy density is still a winning attribute of hydrocarbons: most notably, powered flight for freight and travel.
We already have two routes to non-fossil hydrocarbons: biological sources, and direct chemical synthesis. Each involves capturing atmospheric CO2, and combining with water, to generate a blend of hydrocarbons.
Now, we already have means of creating hydrocarbons suitable for flight (e.g. Jet-A and Jet-A1 fuels). And there are already demonstration plants that have closed-loop generation of synthetic hydrocarbons, for use in electricity-grid-balancing, by using surplus electricity to synthesise methane, which is then burnt in gas turbines when required. Similarly, Tony Marmont's team have been synthesising petrol (gasoline) from air, water, and electricity.
However, none of those things mean that hydrocarbons necessarily have much of a future, beyond plastics production. Because hydrocarbon-powered aviation has a lot of environmental problems beyond just CO2 emissions, in particular it makes other contributions to exacerbating global warming. And there are lots of options for energy storage within the electricity supply chain.
The following is multiple choice question (with options) to answer.
As the use of alt bio fuels increases, the use of what will decrease? | [
"wind power",
"solar heat",
"hydro-electric power",
"non regenerating fuels"
] | D | natural gas is a source of heat by burning |
OpenBookQA | OpenBookQA-4528 | identification, minerals
Title: How can chemists distinguish pure chemical element specimens that look almost "the same" as well as what deposit is what in a multimineral mined rock? As a non chemist I am most often charmed when visiting Wikipedia articles of chemical elements and see images of very pure specimens of element after element, proton by proton, and often also metal cube specimen made from smithing similar pure deposits.
The wiki article Periodic table allows me to do so easily; here are some elements I found looking almost the same and don't think I personally could distinguish between them without some instrument:
molybdenum and manganase
titanium and chromium
rutenium and cadmium
sodium and aluminium
silicone and germanium
The following is multiple choice question (with options) to answer.
What is made of minerals? | [
"Stonehenge",
"car engines",
"alcohol",
"electricity"
] | A | rock is made of minerals |
OpenBookQA | OpenBookQA-4529 | everyday-life, ice
Title: Why are some parts of this ice block cloudy and other parts clear? I had a sprain in my leg a few days back. The doctor recommended dipping my foot alternately in ice-cold and hot water to aid blood circulation. It is here that I discovered something interesting.
The picture above shows the piece of ice that was put in the bucket. The above picture shows the ice cube from above.
If you look at the large piece of cube from the side (see below), you can see that the upper part of the cube, that was near the open surface of the container in which the ice froze, seems to be almost transparent and has a crystalline appearance. The lower part does not have this appearance, and it is white and opaque.
Why is there a difference in the layers of ice in the large cube? Is it because the water was from tap and not completely pure? The water was put in the refrigerator for a period greater than 12 hours, so the ice has frozen properly. Can anyone explain this unique structure of ice? I've never seen this before.
Update:
This update is to simply demonstrate the bubble formation in the ice,which causes the cloudiness. Out of the two answers, I had accepted the one by @IliaSmilga . Today, the ice formed demonstrated this idea clearly. Given below are the pictures in which the bubbles of dissolved gas are clearly visible.
The following is multiple choice question (with options) to answer.
A lake with two buckets of ice water poured into it each day will likely | [
"shrink",
"dehydrate",
"swell",
"drain"
] | C | as the amount of water in a body of water increases , the water levels will increase |
OpenBookQA | OpenBookQA-4530 | That would be a total of 5x30 + 3x40 + 2x60 = 390 plants (with an arbitrary factor that we'll set to 1 without loss of generality).
The amount of highbush is 5x30 = 150.
The amount of lowbush is 3x40 = 120.
The amount of hybrid is 2x60 = 120.
If the opossums didn't care, they would likely eat blueberries in this ratio (null hypothesis H0).
The total that we have observed the opossums to eat is 5% x 150 + 10% x 120 + 20% x 120 = 43.5 plants.
They eat 5% large, which a corresponding fraction of 5% x 150 / (5% x 150 + 10% x 120 + 20% x 120) = 17%
They eat 10% low for 10% x 120 / (5% x 150 + 10% x 120 + 20% x 120) = 28%
They eat 20% hybrid for 20% x 120 / (5% x 150 + 10% x 120 + 20% x 120) = 55%.
Checking... yes the total is 100%.
What we see is that the opossums prefer hybrid by far.
Small blueberries are their second choice.
Last edited:
#### anemone
##### MHB POTW Director
Staff member
Hi anemone!
What do you mean by the symbol E?
Anyway, you've found that the opossums eat 45.8% large and 54.2% small for a total of 100%.
But... what happened to the hybrid blueberries?
By the symbol E, I meant the blueberries (all 3 types of them) that are eaten by opossums...
That would be a total of 5x30 + 3x40 + 2x60 = 390 plants (with an arbitrary factor that we'll set to 1 without loss of generality).
The amount of highbush is 5x30 = 150.
The amount of lowbush is 3x40 = 120.
The amount of hybrid is 2x60 = 120.
If the opossums didn't care, they would likely eat blueberries in this ratio (null hypothesis H0).
The following is multiple choice question (with options) to answer.
Before spring can arrive a squirrels must gather nuts to make it through | [
"December",
"rocks",
"blankets",
"microwaves"
] | A | squirrels gather nuts in the autumn to eat during the winter |
OpenBookQA | OpenBookQA-4531 | human-anatomy
Title: Why is a penis an organ? According to Wikipedia an "An organ is a group of tissues with similar functions". I don't know anything about anatomy but it doesn't seem to me that a penis can be delimited somewhere to form a "group". Therefore I do not understand why a penis is considered an organ.
Can you explain it to me ? Frankly, that's a terrible definition by Wikipedia.
Merriam-Webster defines an organ as:
a differentiated structure (such as a heart, kidney, leaf, or stem) consisting of cells and tissues and performing some specific function in an organism
or
bodily parts performing a function or cooperating in an activity
The important defining feature of an organ is not that the tissues have similar functions but that, together, the tissues comprise a functional whole that achieves some end goal.
For the penis, it consists of multiple tissues with different functions:
(from https://www.ncbi.nlm.nih.gov/books/NBK525966/figure/article-20668.image.f1/ - original from Gray's Anatomy)
The different tissues pictured here: the fibrous envelope, the corpora cavernosa, the septum pectiniforme, the urethra and blood vessels, the nervous tissue in the skin: all of these tissues have different individual functions: structural, erectile, carrying urine or semen, etc.
The key that unifies them into an organ is that the functions of the penis at the organism level (principally sexual function) are not served by any of these tissues alone, but rather by their combination in a full structure: an organ.
Ultimately, organ definitions are somewhat opinion-based: people are lumpers and splitters, so you might find conflicting definitions for which groupings of tissues reflect distinct organs, but I think by most standards you would find the penis to be considered a distinct organ, affiliated with but distinct from the primary sex organs and associated glands.
The following is multiple choice question (with options) to answer.
What your body looks like and how it functions is something that is | [
"received from one's parents",
"passed away from Earth",
"passed down from eggs",
"passed down from tomorrow"
] | A | the number of body parts of an organism is an inherited characteristic |
OpenBookQA | OpenBookQA-4532 | human-biology, biochemistry, molecular-biology, cell-membrane, pulmonology
Title: How does lipoid pneumonia lead to acute respiratory distress syndrome (ARDS)? How does lipoid pneumonia lead to acute respiratory distress syndrome (ARDS)?
The vaping illnesses that have been happening on the news in the United States are being caused by the federal prohibition on marijuana. Smugglers will legally go to recreational marijuana dispensaries in legal states and purchase cartridges that contain about a gram of "wax". Proper cartridges will use polyethylene glycol, polypropylene glycol, or vegetable glycerin to suspend the THC for vaporizing, but the smugglers have been known to open up the tank and remove some of the wax and refill the remaining volume with Vitamin E Oil. These tampered cartridges are then sold on the black market to recreational and medical consumers in illegal states.
The CDC Report: "Outbreak of Lung Injury Associated with the Use of E-Cigarette, or Vaping, Products"
Edit: So, I was on some conspiracy shtuff when I wrote this post because I was worried about impurities in my vapes killing me. I don't want to take this down because I want my cognitive distortion to remain visible as a reminder of how we can succumb to biased reasoning. Also, the answer I marked correct contextualized the fragmented information of which I was aware and attempted to give me an improved framework for understanding the terms I was using incorrectly as a layman. There are several ways to get ARDS (sepsis, pneumonia, trauma, pancreatitis, etc). Pathophysiologically, they all converge at alveolar insult. So however it happens, there's alveolar insult, cytokine release that recruits neutrophils, and the activated neutrophils release toxic mediators that destroy the alveolar membranes. So for your question specifically, the mineral oil in the vape cartridges (theoretically) is instigating an inflammatory reaction that destroys alveolar membranes.
The following is multiple choice question (with options) to answer.
What causes direct damage to the lungs? | [
"drinking alcohol",
"consuming ignited tobacco",
"eating feces",
"swimming"
] | B | smoking causes direct damage to the lungs |
OpenBookQA | OpenBookQA-4533 | ornithology
Title: How do birds learn their tunes in isolation from their own species? I wonder what a bird would sing if it didn't have its parents around (or any other birds for that matter) to learn its chirping sounds from.
I'm interested in how a bird would sing...
in complete isolation from creatures communicating through sound;
in isolation from its own species, but with other birds;
in isolation from all birds (other animals and creatures are there for it)
For example,
Would a bird even feel the need to speak up if there wasn't any other vocalizing creature around?
Would a bird learn other species' signals? Would it only learn from one species, the one which it would think of a fitting mate?
Would a bird try to mimic a non-flying creature's signals?
These are similar questions, but if you think they should be separated, let me know in the comments. Birds have to learn their song patterns.
They are able to chirp, but the songs with "meaning" are learned from their parents or whatever they learned to be their "parent".
Here is a paper that related bird song learning to human learning (of speech, for example).
Birds brought up by parents from another species learned to sing their songs.
There are many birds that learn to imitate other animals or sounds, so in isolation from all birds they will probably do this.
I can't recall where, but I read a paper once, where little finches brought up by humans developed a song resembling the "Hello there, now there's food", their caretaker always greeted them with. (Not the speech, but the overall sound pattern.) They might not understand the signals, but they try to communicate nevertheless. Some birds use sound from other species to mock others, scare them off or lure them into thinking they might be more powerful than they are.
Birds brought up in total isolation do sing, but not the typical songs you know from their species. Deaf birds who can't hear themselves, though, do not (always) sing.
The following is multiple choice question (with options) to answer.
Two parakeets, each in a separate house, each in a windowless room, may share information through | [
"squawks",
"shrugs",
"seeds",
"notes"
] | A | sound can be used for communication by animals |
OpenBookQA | OpenBookQA-4534 | 3. Jun 16, 2009
### HallsofIvy
Writing "M" for male and "F" for female, there are 25= 32 ways to write 5 letters, each being either an "M" or an "F". Of those 32, exactly one is all "M"s and exactly one is all "F"s.
Knowing that there is at least one female drops "MMMMM" leaving 31 possibilities. "FFFFF" is one of those: probability 1/31.
If we write the dogs in order of age, then knowing that the oldest dog is female means that we are looking at lists of 5 letters, from "M" or "F", with the first letter being "F". Obviously in all possible lists of 5 "M"s or "F"s, exactly half, 16 start with "F" and half with "M" so knowing that "the oldest dog is a female" throws out half the possible lists, leaving 16. one of those is "FFFFF" so the probability of "all females" is now 1/16.
There is no "dilemma" here. "The oldest dog is female" gives you more information than "at least one of the dogs is female".
4. Jun 16, 2009
### fleem
First breeder:
Since its given that there is at least one female, the question, "what is the probability that all five are female when one is female" means the same thing as the question, "What is the probability that the remaining four are female". The probability that the remaining four are female is 1/16, and thus the probability that all five are female (given that one is female) is 1/16.
Second breeder:
The temptation here is to assume there might have been intelligent pre-selection of dogs in the group, by the store owner. However the OP makes it pretty clear, I think, that there was no such pre-selection, and that these are ALL the dogs from a given litter. So the sex of a randomly selected dog does NOT change the probability of the sex of another dog in the litter. Each is a separate coin toss. So the fact that the oldest is female works the same as "there is at least one female". So like with the first breeder case, the probability of the remaining four all being female is 1/16.
5. Jun 16, 2009
The following is multiple choice question (with options) to answer.
A creature of a certain age lays a clutch, so it is probably a | [
"deer",
"hare",
"falcon",
"bear"
] | C | some adult animals lay eggs |
OpenBookQA | OpenBookQA-4535 | evolution, natural-selection, mutations, sexual-reproduction
The testis seems to be the Oven in which genetic variation is baked. The rapid turnover of spermatogenesis, whereby each primary spermatocyte finally results in 4 sperms (Compared to One Ovum resulting from each primary Oogonia), that's beside the very large number of sperms produced daily, that continues for years and year. While with the Oogenesis everything really finishes at the foetal life, the remaining is just maturation steps, nothing is new as far as change of genetic material inside the Oocytes is concerned, this is the state throughout most of the female's life.
When I look at the seminiferous tubules, and see all those layers of spermatocytes leading to sperms, I tend to think that there is even some small scale natural selection, that bad mutated germline cells would die off, and only the ones with good genomes would survive all the stages of spermatogensis, and possibly the ones with beneficial mutation might have an advantage in survival in that milieu and even might have better chances of fertilizing the ovum?
Not only that, the testis seems to be more exposed to stressors inside the body and even to direct external environmental stressors, while the Ovaries lying deep inside, seem to be more protected. The Oocyte actually "selects" one sperm, so it's rule is selective rather than productive of change.
All of that makes one think that it is the male germline cells that could mediate high mutation rate in response to stressors, or even without stressors by virtue of the very high production rate of germline cells for very long periods of time. It seems that this is the real source of beneficial mutations that would ultimately drive evolution.
The following is multiple choice question (with options) to answer.
This animal evolved to reproduce using protective containers instead of live little entities: | [
"rhino",
"hamster",
"platypus",
"mongoose"
] | C | some adult animals lay eggs |
OpenBookQA | OpenBookQA-4536 | zoology, digestive-system, pets
Title: Is it safe to feed an adult fire salamander with slime maggots? As a reminder, maggots feed of a flesh, while fire salamander consumes his prey alive, without killing it.
Can it happen that the maggot will start eating the salamander from the inside? Although I am afraid I don't know much about fire salamanders specifically, it is certainly possible for ingested fly larvae (or larvae hatching from ingested eggs) to survive ingestion and subsequently cause intestinal damage. Parasitic infestation by fly larvae that grow inside the host while feeding on its tissue is called myiasis. Enteric myiasis (also called gastric, rectal, or intestinal myiasis to indicate the affected part of the digestive system) occurs occasionally in humans following the ingestion of cheese infested with cheese fly maggots. Casu marzu, a traditionally produced Sardinian cheese, is supposed to have live cheese fly maggots in it, and cases of bloody diarrhoea following its consumption are known. If they're dead the cheese is considered unsafe to eat (although personally I'd correct that to 'more unsafe').
The following is multiple choice question (with options) to answer.
Salamanders might be found under | [
"garden statues",
"spaceships",
"business suits",
"love"
] | A | a salamander eats insects |
OpenBookQA | OpenBookQA-4537 | zoology
Capybara, rabbits, hamsters and other related species do not have a complex ruminant digestive system. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft fecal pellets of partially digested food are excreted and generally consumed immediately. Consuming these cecotropes is important for adequate nutritional intake of Vitamin B12. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the feces of their mother to obtain the bacteria required to properly digest vegetation found on the savanna and in the jungle. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to obtain any nutritional value from plants.
Eating garbage and human feces is thought to be one function of dogs during their early domestication, some 12,000 to 15,000 years ago. They served as our first waste management workers, helping to keep the areas around human settlements clean. A study of village dogs in Zimbabwe revealed that feces made up about 25% of the dogs’ overall diet, with human feces making up a large part of that percentage.
Coprophagia
Daily rhythms of food intake and feces reingestion in the degu, an herbivorous Chilean rodent: optimizing digestion through coprophagy
Coprophagia as seen in Thoroughbred Foals
The following is multiple choice question (with options) to answer.
Rabbits are herbivores, meaning they only | [
"eat metal",
"eat people",
"consume vegetation",
"eat dinosaurs"
] | C | rabbits eat plants |
OpenBookQA | OpenBookQA-4538 | zoology
Capybara, rabbits, hamsters and other related species do not have a complex ruminant digestive system. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft fecal pellets of partially digested food are excreted and generally consumed immediately. Consuming these cecotropes is important for adequate nutritional intake of Vitamin B12. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the feces of their mother to obtain the bacteria required to properly digest vegetation found on the savanna and in the jungle. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to obtain any nutritional value from plants.
Eating garbage and human feces is thought to be one function of dogs during their early domestication, some 12,000 to 15,000 years ago. They served as our first waste management workers, helping to keep the areas around human settlements clean. A study of village dogs in Zimbabwe revealed that feces made up about 25% of the dogs’ overall diet, with human feces making up a large part of that percentage.
Coprophagia
Daily rhythms of food intake and feces reingestion in the degu, an herbivorous Chilean rodent: optimizing digestion through coprophagy
Coprophagia as seen in Thoroughbred Foals
The following is multiple choice question (with options) to answer.
which is most likely to be eaten by a rabbit | [
"trout",
"dandelions",
"field mice",
"spiders"
] | B | rabbits eat plants |
OpenBookQA | OpenBookQA-4539 | evolution, botany, photosynthesis, speculative, chloroplasts
Title: Why do plants have green leaves and not red? I know plants are green due to chlorophyll.
Surely it would be more beneficial for plants to be red than green as by being green they reflect green light and do not absorb it even though green light has more energy than red light.
Is there no alternative to chlorophyll? Or is it something else? Surely it would be even more beneficial for plants to be black instead of red or green, from an energy absorption point of view. And Solar cells are indeed pretty dark.
But, as Rory indicated, higher energy photons will only produce heat. This is because the chemical reactions powered by photosynthesis require only a certain amount of energy, and any excessive amount delivered by higher-energy photons cannot be simply used for another reaction1 but will yield heat. I don't know how much trouble that actually causes, but there is another point:
As explained, what determines the efficiency of solar energy conversion is not the energy per photon, but the amount of photons available. So you should take a look at the sunlight spectrum:
The following is multiple choice question (with options) to answer.
Which plant absorbs the most sunlight? | [
"the one that dates grow on",
"the one that eats insects",
"the one that grows in the tundra",
"the one that ladybugs like the best"
] | A | as the size of a leaf increases , the amount of sunlight absorbed by that leaf will increase |
OpenBookQA | OpenBookQA-4540 | newtonian-mechanics, forces, classical-mechanics, free-body-diagram
Title: If an object would be too tough to puncture while static, is it possible to pierce it while holding still and having it move toward you? In The Lord of the Rings it is claimed that no man has the strength to pierce the skin of the giant spider Shelob. In a dramatic turn of events, Shelob lunges at Sam with such force that she pierces herself with Sam's sword.
This seems physically impossible to me, assuming the real-world laws of physics are in effect. Wouldn't Sam need the strength to hold the sword in place in order to actually pierce, and by Newton's third law and the above claim, require impossible strength? Maybe this has something to do with impulse, which I never fully understood. There are three ways ways this might work, all of which using Shelob's own strength.
First, as noted in other answers, the sword could have been driven down until the hilt struck the floor and was braced that way.
The sword could have been held straight up with the arms and legs locked and the crosspiece of the sword pressed against the hands. In this stance, a body could withstand more force than the muscles could actively exert, and thus act as sufficient brace against Shelob's own superior strength.
The text seems to support that Shelob's body was hard. Piercing thus is a matter not of force, per se, but of impulse: mv = Ft. The harder the shell, likely the more a quick impulse will break it. Shelob could have moved with such speed against a thrust that the impulse time was shortened, and the strength of Sam's own thrust multiplied because of the shortened interval, since that equation rearranges to F = mv/t.
The following is multiple choice question (with options) to answer.
A suit of armor pulls which of these to it easily? | [
"a stick",
"a paper leaflet",
"a fridge decoration",
"a wooden cog"
] | C | metal is sometimes magnetic |
OpenBookQA | OpenBookQA-4541 | electromagnetism, magnetic-fields, everyday-life
Title: How is magnetism ''conducted'' through a non-magnetic metal? I have a ball of metal about an inch in diameter and a concave disc of another metal (which is magnetic) around the ring of the disc (about $12 {\rm mm}$ in diameter). I don't know which metals they are. The ball is not magnetic on its own. That is paramagnetism, right?
The magnetic ring is strongly attracted to the surface of the ball, 'sticking' to it. However, I can stick a paperclip on the opposite side of the ball as if it has become magnetic itself, until I remove the magnetic ring from the ball.
When I wave the paperclip the same distance from only the ring itself, I feel no force at that distance.
Has the strong magnetic field of the ring caused a temporary magnetic alignment through the metal of the ball, allowing the paperclip to be attracted to it while the ring remains? The phenomenon you describe is ferromagnetism not paramagnetism.
Ferromagnetic materials like iron behave as if they contain many tiny bar magnets (called magnetic domains if you're interested to pursue this further), but because the magnet domains are aligned randomly the fields cancel out and there is no net magnetic field.
However if you put a ferromagnetic material in a magnetic field the external field will cause partial alignment of the magnetic domains. This induces a magnetic field in the originally unmagnetised iron, and that's why your paper clip sticks to the ball. However if you remove the external magnetic field the domains will go back to their original alignment, the net magnetic field will go back to zero and the paper clip will fall off again.
If you apply a very strong field and/or combine it with heating and cooling you can permanently change the alignment of the magnetic domains so they remain aligned when the external field is removed. This is how you make permanent magnets.
The following is multiple choice question (with options) to answer.
This is likely magnetic: | [
"the innards of a cow",
"the innards of an iPhone",
"the innards of a head",
"the innards of a tree"
] | B | metal is sometimes magnetic |
OpenBookQA | OpenBookQA-4542 | machine-learning, classification
Title: How do I approach a classification problem where one of the classes is defined by 'not any of the others' Suppose that I am interested in three classes $c_1$, $c_2$, $c_3$. But my dataset actually contains several more real classes $(c_j)_{j=4}^n$.
The obvious answer is to define a new class $\hat c_4$ that refers to all classes $c_j$, $j>3$ but I suspect this is not a good idea since the samples in $\hat c_4$ will be rare and not very similar to each other.
To visualize what I'm trying to say, suppose I have the following two variable space and the classes $c_1$, $c_2$, $c_3$, $\hat c_4= \bigcup_{j=4}^n c_j$ are depicted in red, til, green and black respectively. This is how I suspect my data would look like.
The following is multiple choice question (with options) to answer.
What would classify students in a class differently? | [
"species",
"favorite animal",
"home planet",
"current school"
] | B | classifying means grouping materials by their properties |
OpenBookQA | OpenBookQA-4543 | human-biology, eyes, vision, human-eye
Title: Superhuman eyesight My ten year old son was reading car number plates that were too fast, too far away and at the wrong angle for any of us to read or even believe that it was possible for him to read. We thought he was lying as he reeled off the whole number plate and not just some. My husband went across the road to prove him wrong and get him to admit he was making it up but he wasn't. We even asked people in the restaurant and waiting staff for their opinion and everyone was blown away. I'm totally astonished and slightly freaked out by his sight and I'm hoping someone can explain for me.
Specifics
The following is multiple choice question (with options) to answer.
Asking a blind person to look at something is rude because they are | [
"unable to speak",
"unable to eat",
"unable to see",
"unable to live"
] | C | seeing is used for sensing visual things |
OpenBookQA | OpenBookQA-4544 | optics, visible-light, everyday-life, diffraction
Addendum 2: Before the comments below were cleaned out, there was some discussion there about the usefulness of this phenomenon as a quick self-diagnostic test for myopia (nearsightedness).
While I Am Not An Opthalmologist, it does appear that, if you experience this effect with your naked eye, while trying to keep the background in focus, then you may have some degree of myopia or some other visual defect, and may want to get an eye exam.
(Of course, even if you don't, getting one every few years or so isn't a bad idea, anyway. Mild myopia, up to the point where it becomes severe enough to substantially interfere with your daily life, can be surprisingly hard to self-diagnose otherwise, since it typically appears slowly and, with nothing to compare your vision to, you just get used to distant objects looking a bit blurry. After all, to some extent that's true for everyone; only the distance varies.)
In fact, with my mild (about −1 dpt) myopia, I can personally confirm that, without my glasses, I can easily see both the bending effect and the sharpening of background features when I move my finger in front of my eye. I can even see a hint of astigmatism (which I know I have; my glasses have some cylindrical correction to fix it) in the fact that, in some orientations, I can see the background features bending not just away from my finger, but also slightly sideways. With my glasses on, these effects almost but not quite disappear, suggesting that my current prescription may be just a little bit off.
The following is multiple choice question (with options) to answer.
Glasses help you | [
"fry ants",
"pay for crimes",
"remedy eyesight issues",
"observe Uranus"
] | C | seeing is used for sensing visual things |
OpenBookQA | OpenBookQA-4545 | human-physiology, digestion, stomach
The stomach accomplishes much of its function by mechanically breaking down the swallowed food particles and mixing them with acid and enzymes into a sort of slurry. To do this, there are three major layers of muscle surround the stomach - from the outside, the longitudinal layer, the circular layer, and the oblique layer. The stomach also has two holes in it - the gastroesophageal opening, coming from the esophagus with the swallowed food/saliva mix, and the pylorus, where the food/acid/enzyme slurry exits into the duodenum, which is the beginning of the small intestine.
Due to the three layers of (rather strong) muscle, the stomach doesn't have a lot of expansion capability once it is filled completely to capacity. Fortunately, this almost never occurs (despite how we may feel after a large meal) because material is always leaving the stomach on its way to enzymatic digestion in the intestines. Additionally, once the stomach is filled to a certain extent, hormones such as leptin are secreted that give you the feeling of being sated, or full, triggering the brain to make you stop eating.
Of course, as we can see with the current epidemic of obesity around the world, the stomach can change its size over time. However, this is a rather slow process (weeks to months to years) of adapting to continuously consuming large meals.
But what would happen if you completely ignored these internal warnings, or were being force-fed, or whatever? Instead of rupturing (the biological equivalent of "exploding"), food would most likely be expelled either into the small intestine or back into the esophagus and back up the way it came down, i.e. causing vomiting.
The following is multiple choice question (with options) to answer.
Digestion is when stomach acid breaks down what? | [
"food essays",
"sustenance",
"water",
"air"
] | B | digestion is when stomach acid breaks down food |
OpenBookQA | OpenBookQA-4546 | proteins, food, digestive-system, amino-acids, digestion
Title: How are proteins reused in the body? Part of what we eat are proteins,
and our body is in part build of proteins.
Are the proteins of the body build based on proteins in food at all?
Are proteins in food directly reused in the body,
or are proteins first disassembled?
How far are they disassembled, randomly in various pieces, or systematically to keep what can optimally be used to build new proteins, while nothing is wasted for energy?
(The question Can proteins/peptides pass through the intestine? and it's answers are related, and provide some context and relevant parts, but is not a duplicate.) Short answer: Indeed the proteins in our body are based on amino acids from external food sources. BUT, proteins up-taken from food are ALWAYS disassembled first into amino acids, through specialized enzymes, proteases, (for instance Pepsin in the stomach's gastric juices and Tripsin in the pancreatic juices), during digestion, in the alimentary canal, (gut). This enables the body's liver to build the proteins most needed by the organism itself, through the processes of transamination, that allows conversion betwixt amino acids, and deamination, that removes N2 from the amino acid, (let's say the "amino" part is removed, and then expelled as urea), to excrete amino acids in excess. In addition this breaking down of external proteins is necessary, since they can act as labels for pathogens, and external organisms in general, and thus would soon be destroyed by the immune system if reused straight away.
The following is multiple choice question (with options) to answer.
Which likely is digested by the body? | [
"fire",
"air",
"twinkies",
"water"
] | C | digestion is when stomach acid breaks down food |
OpenBookQA | OpenBookQA-4547 | Suppose you have a tall building with $n$ floors. The top floor is either yellow or blue.
Suppose the top floor is yellow and imagine popping this floor off the building. How many buildings on $n-1$ floors could remain? Since the top floor being yellow placed no additional restrictions on the other floors (aside from the universal one that two blue floors cannot touch), there are $D_{n-1}$ ways to color the remaining floors.
Suppose the top floor is blue. In this case, I know for certain the floor beneath it is yellow. Pop these top two floors off and ask how many buildings on $n-2$ floors could remain. Again, these floors could be colored using any legal configuration, so there are $D_{n-2}$ ways to do this.
Taken together, we get the recursion $D_n = D_{n-1} + D_{n-2}$ for $n \geq 2$. Since the recursion goes back two steps, we need to compute the values of $D_0$ and $D_1$ directly (the recursion won't help us find these first two values). There are no buildings having zero floors and there are just two having one floor, so $D_0 = 0$ and $D_1 = 2$ are the initial conditions.
Let $Y_n$ denote the number of colorings under the extra condition that the upper floor has color yellow, and let $B_n$ denote the number of colorings under the extra condition that the upper floor has color blue.
Then for $n=1,2,\dots$ we have the following equalities:
• $Y_{n+1}=D_n$
• $B_{n+1}=Y_n$
• $D_n=Y_n+B_n$
Now observe that: $$D_{n+2}=Y_{n+2}+B_{n+2}=D_{n+1}+Y_{n+1}=D_{n+1}+D_n$$
The initial conditions are $D_1=2$ and $D_2=3$ which are not difficult to find.
The following is multiple choice question (with options) to answer.
The greater of number of inhabited buildings in a space | [
"the brighter the stars",
"the fewer visible stars",
"the more boring the stars",
"the more stars in the sky"
] | B | as distance to a city decreases , the amount of light pollution will increase |
OpenBookQA | OpenBookQA-4548 | universe, cosmology
Conclusion
I'm sure you could think up a lot of different types of other energies you might want to include in this, but hopefully you see the point I'm driving at. They're all completely negligible. The arguably largest contribution comes from radiation and that's been shown to be $0.005\%$ of the Universe's mass-energy budget. What we see is that the Universe is dominated by Dark Energy, has a bit of Dark Matter, a small amount of atoms, and negligible amounts of the rest of everything else. And overtime, the Dark Energy portion of that pie chart will get bigger and bigger until we'll be able to throw out atoms and dark matter from the plot as well since they'll be just as insignificant as neutrinos and radiation are now.
The following is multiple choice question (with options) to answer.
Our only star provides us with energy that is | [
"temporary",
"inferior",
"expensive",
"reusable"
] | D | solar energy is a renewable resource |
OpenBookQA | OpenBookQA-4549 | resources, soil
Title: Is soil a renewable resource? My geology textbook tells me that soil is not renewable, and I agree with this, but there was some question in my class as to whether this is true.
Some soils take more than a human lifetime to regenerate. However, in crop production, it seems as if soil can be regenerated with additives.
In the scientific community of soil scientists, is soil considered a renewable resource by most of those scientists? Is there strong evidence to support this? Soil is an interesting case because although it is non-renewable (at any useful rate) as a 'bulk material' once removed from the ground, the nutrient content of soil can be renewed with fertilizers.
What a soil-scientist would understand as 'soil' is ultimately produced from the physical and chemical breakdown of solid bedrock at the base of the soil horizon. The rate at which this happens for natural soil production can vary substantially depending on the climatic conditions and other factors, but typically could range from 0.1 to 2.0 mm/yr.
In many intensively farmed regions, (top)soil is being removed by erosion much faster than it is being replaced by natural process. Removal of vegetation cover is enough to expose bare soil to rainsplash erosion at rates much greater than it is renewed. Once soil is bare, it becomes much more susceptible to erosion.
I think the additives you are referring to replenish the nutrient content of the soil, and not the the bulk material that would be produced by bedrock decomposition. With careful management, the fertility of existing soil can be maintained. But if the soil is allowed to be washed off or erode, for all practical purposes, the rate of replenishment is not fast enough for it to be classed as renewable in that sense.
This site has links to more aspects surrounding this issue.
The following is multiple choice question (with options) to answer.
What is a renewable source? | [
"electricity from coal power plants",
"oils made from whale blubber",
"energy from the yellow dwarf star closest to us",
"gasoline made from fossils"
] | C | solar energy is a renewable resource |
OpenBookQA | OpenBookQA-4550 | evolution, biochemistry, plant-physiology, plant-anatomy, life
Title: Plants without bacteria? is it theoretically possible? I know from school, that all live on the Earth need bacteria as low-level "machines" that break down/extract/convert/produce chemical elements and combinations, other high-level organisms needed. But it is a natural way.
But is it possible to have a world with plants (without mammals or microorganisms and without bacteria) that could exist in the long term. Saying the atmosphere of these world has already enough nitrogen, oxygen and CO2, and of course there is water.
What could break this artificially created world with such conditions (say the world created not from low-level living structures)?
Could bacteria emerge in the world? This is the sort of question that should be considered from more than one perspective. Since this is speculation, take it as a given that there is a lot of 'what if' here.
I doubt most animals and plants can do entirely without bacteria - as you say most of the essential nutrients come from bacteria, who fix nitrogen. If only plants were left on earth, eventually the plants would use up all the nitrogen and they would have to find a way to fix more.
Can bacteria emerge from just a world of plants? I don't think viruses arise spontaneously, but since genomes often have viruses embedded in them, over the course of a billion years or so, its possible since bacteria and viruses continue to be impressed upon our genomes. Would it happen in time? Most would be skeptical whether that timing could work out.
In practice it would be hard to create a world like this. I would be interested to see whether you could sterilize the microorganisms off of seeds without killing the plant for instance. If you're asking about a small sterile environment with only plants, you could do it by adding the nutrients the plants need and giving them sunlight. Such self sustaining systems have been made with cyanobacteria and i'd be surprised if plants could not be included. But these are closed systems and judged by limited amounts of time, so whether this is an answer to your question is not clear. Here it looks like some water plants and fish have been done. If there was a plant that created CO₂ at an adequate rate its possible.
The following is multiple choice question (with options) to answer.
Plants would be unable to stand if they lacked | [
"multiple leaves supported on its torso",
"gel that form shapes",
"the ability to flower nightly",
"tiny structures inside the support"
] | D | a stem is a source of support for a plant |
OpenBookQA | OpenBookQA-4551 | species-identification, botany, fruit
Title: Identify this unusually-shaped, orange-colored fruit that grows in pairs? The photos below were taken on the island of Penghu in the Taiwan straight in October. This was in a public place and the small tree (about 3 meters tall, trunk perhaps 8 to 10 cm diameter) had probably been planted, so we can't presume it to be indigenous.
Each fruit was about 6 or 7 cm long, the skin was bright orange and seemed a bit waxy. The shape was a little bit like a banana-shaped American football in that it was divided into four quadrants. They attach to a stem in pairs and extend horizontally (sideways) rather than hang down.
Question: What could this gravity defying fruit-bearing tree be?
The first image is cropped, zoomed and sharpened in order to highlight textures. The seed pods reminded me of the Apocynaceae, so I searched for "apocynaceae china" and found this University of Hawaii page where it is identified as Stemmadenia litoralis. However, a little more looking it seems Tabernaemontana litoralis may be the preferred name. There is some debate here. This book may hold the final answer regarding the genus.
Your picture of the fruit is one of the best one I could find on the internet. There is another good one here with other pictures of the plant.
You were also correct that as a planted tree it might not be native. This plant comes from Central America.
The following is multiple choice question (with options) to answer.
Sycamores have the worlds largest | [
"trunk",
"friends",
"leaves",
"location"
] | A | a stem is a source of support for a plant |
OpenBookQA | OpenBookQA-4552 | Note:
Depending on where, and how frequently, you round during this function, your answers may be off a few cents in either direction. Try rounding as few times as possible in order to increase the accuracy of your result.
The following is multiple choice question (with options) to answer.
Which is most accurate? | [
"melting is when solids are heated above their melting point; freezing is when solids are cooled from liquid to solid",
"melting is when solids are heated above their melting point; melting is when solids are cooled from liquid to solid",
"freezing is when solids are heated above their melting point; melting is... | A | melting is when solids are heated above their melting point |
OpenBookQA | OpenBookQA-4553 | electromagnetism, charge
You may ask why it is then so contrary to speak that two opposite charges cancel each other. No objection. All I want you to remember is that it is the net charge that is zero. Individually the charges are not zero. Take the example of an ionic crystal, say $NaCl$, where $Na^+$ and Cl^-$ ions are tightly held together by electrostatic attraction. Both ions have equal and opposite charges. If the interaction between the two lead to the individual destruction of charges (losing property as a charge), then how the solid continues to be so brittle. There is always interaction between the two ions. This means the interaction between the two charges do not cause the charges to lose their charge. It's the effective charge that is zero. We then speak about a system, not about individual charges.
The following is multiple choice question (with options) to answer.
if two objects have the same charge then those two materials will effect each other how? | [
"pull together",
"attract",
"unattract",
"bug repellent"
] | C | if two objects have the same charge then those two materials will repel each other |
OpenBookQA | OpenBookQA-4554 | behaviour
References
Shimada M, Watanabe H, Komine Y, Kigawa R, Sato Y. New records of Ctenolepismacalvum (Ritter,1910) (Zygentoma, Lepismatidae) from Japan. Biodivers Data J. 2022 Nov 3;10:e90799. doi: 10.3897/BDJ.10.e90799. PMID: 36761636; PMCID: PMC9836529.
Kulma M, Bubová T, Davies MP, Boiocchi F, Patoka J. Ctenolepisma longicaudatum Escherich (1905) Became a Common Pest in Europe: Case Studies from Czechia and the United Kingdom. Insects. 2021 Sep 10;12(9):810. doi: 10.3390/insects12090810. PMID: 34564251; PMCID: PMC8471186.
Querner P, Szucsich N, Landsberger B, Erlacher S, Trebicki L, Grabowski M, Brimblecombe P. Identification and Spread of the Ghost Silverfish (Ctenolepisma calvum) among Museums and Homes in Europe. Insects. 2022 Sep 19;13(9):855. doi: 10.3390/insects13090855. PMID: 36135556; PMCID: PMC9505982.
The following is multiple choice question (with options) to answer.
A cousin to the mole survives on | [
"plants",
"rocks",
"rats",
"rabbits"
] | A | meadow voles eat plants |
OpenBookQA | OpenBookQA-4555 | cellular-respiration
Title: Do cold blooded animals generate any heat? In explaining energy and work to an 8 year-old I said that all conversion of energy generates heat as a by-product. For example, cars generate heat in their engines and running generates heat in our bodies. Then the 8 year-old said, except for cold-blooded animals.
So my question is, do cold-blooded animals generate any heat in their conversion of stored energy (food, fat, etc) into motion? If they generate heat, why are they cold-blooded? They do generate heat. They just do not SPEND energy specifically on heating their bodies by raising their metabolisms. This is a form of energy conservation. The metabolic rate they need to live is not nearly enough to heat their bodies.
An example of spending energy to heat the body is seen in humans shivering. Here muscle is activated not for its usual purpose, but to function as a furnace. "Warm-blooded" and "cold-blooded" is somewhat a misnomer. The correct way to think of it is...
Endotherm or ectotherm. Does the heat primarily come from within (endo) or from the surroundings (ecto). Endothermic animals include mammals. Most of their body heat is generated by their own metabolisms. Ectothermic animals include reptiles and insects. They absorb most of their body heat from the surroundings. This is not the same as saying they let their body temperature fluctuate with their surroundings, some avoid this by moving around to accomodate themselves.
Homeotherm or poikilotherm. Homeotherms want to maintain homeostasis for their body temperatures. They don't want it to change. Poikilotherms do not exhibit this behaviour, instead their body temperatures vary greatly with the environment.
We can have endotherm poikilotherms, such as squirrels, who let their body temperature drop while hibernating. Endotherm homeotherms, such as humans, where temperature is constant by means of complex thermoregulation. Ectotherm homeotherms, such as snakes (moving into shadow or into the sun to regulate temperature), and ectotherm poikilotherms, such as maggots.
The following is multiple choice question (with options) to answer.
Shivering is when an animal creates heat by shaking to keep the body what? | [
"frozen",
"freezing",
"cold",
"agreeable temperature"
] | D | shivering is when an animal creates heat by shaking to keep the body warm |
OpenBookQA | OpenBookQA-4556 | earth-history, mass-extinction, geobiology, evolution, ecology
Title: Why haven't weeds overtaken the entire planet? Given how rapidly weed plants spread and grow, choking out all other plant life, how come after millions of years we haven't ended with forests full of thistle or pokeweed, as opposed to pines or oak trees? A weed is just a plant where you do not want it. Totally a matter of context. Tumbleweeds are non-native, introduced centuries ago. I assume you mean the invasive species of plants that have been spread by humans and are disrupting ecologies throughout most of the world
Until recently, these plants we consider weeds were limited in their range to home environments simply by geographic barriers and surrounding unfriendly environments. And the natural consumers, parasites and competitors in the home environments had adjusted to these plants and kept them in check.
When non-native plants are introduced into a new environment by humans, most of them do not thrive, but occasionally a plant is wildly successful. Eventually the potential consumers, parasites and competitors in that new environment will adjust through evolution. But the tragedy is that many or most of the original species will be destroyed before that balance is restored in a new, way more simplified form. The landscape itself may be totally changed. Removal of a key original species can cause great change too: How Wolves Change Rivers.
Not only will many ecologies be reduced to much simpler versions, even if they eventually conquer the invasive plant, those simplified ecologies will closely resemble each other, if their geography is similar, even if on the other side of the world. If humans were to totally stop transplanting invasive species (collapse of civilization?), diversity would return after millions of years. We know this from Extinction Events.
So to answer you question, weeds before human intervention generally did not take over in their home environments because the potential weeds and their natural consumers, parasites and competitors all evolved together in a quasi-equilibrium. Now, however, most ecologies throughout the world are out of equilibrium because of environmental change and/or invasive species. This will inevitably lead to simplified, usually less robust, weedy ecologies throughout the world. That reduction in diversity might as well be considered a permanent situation compared to the timescale of civilization.
The following is multiple choice question (with options) to answer.
If a species of plant or animal ceases to exist on earth, either by natural causes or by activities of humans, the loss of the plant or animal | [
"reversible extinction",
"cannot be undone",
"reversible",
"a subspecies"
] | B | if all members of a species cannot produce offspring then that species will likely become extinct |
OpenBookQA | OpenBookQA-4557 | arachnology
Title: Can dead scorpions still sting? I found a dead scorpion on the sidewalk today, and brought it home, being careful not to touch its stinger. Bees can sting even after they are dead, if you step on them in such a way that it pushes their stinger out.
Does the same apply to scorpions? Do I need to be careful not to touch its stinger? Yes, the bark scorpion can still sting after death. I learned this myself after stepping on one. As I make a nightly habit of patrolling inside my home for their presence, I can conclude the offender had died within 12 hours of my stepping on it. When they die their tails stretch straight behind their bodies, this was the position I found it in.
The following is multiple choice question (with options) to answer.
red hornets can sting you multiple times with their | [
"poison sack",
"knife",
"spears",
"rears"
] | D | a stinger is used for defense by a wasp |
OpenBookQA | OpenBookQA-4558 | theoretical-biology, hematology, red-blood-cell
**As an intern, I once had the very sorrowful experience of admitting an healthy appearing, exuberant 4 year old child to the pediatric surgical service. The only presenting symptom was that the child started squatting during exertion (not good), and on exam, had a murmur which was caused by aortic stenosis. This was long before imaging studies were as sophisticated as they are now. The pediatric cardiac surgeon took him to the operating room (OR) to replace the valve, but there was so much atherosclerotic aortic damage that there was no healthy tissue which could hold sutures in place. The child died in the OR. I don't know what would have been done today, but had the child stayed home, they might have had a couple more years with the parents, who hoped for an uneventful procedure. So the exercise involved in this answer was fun, but the memory it brought back is still quite sad.
The following is multiple choice question (with options) to answer.
Which would likely cause an injury to a baby? | [
"a bath",
"a pacifier",
"a bottle",
"a wasp"
] | D | a stinger is used for defense by a wasp |
OpenBookQA | OpenBookQA-4559 | food, eggs, allergies
Title: Is it possible to be allergic to the yolk of an egg but not the egg white? At lunch one day, my friend had a hard boiled Easter egg. When he pealed it he squeezed the yolk, or yellow part, of the egg out. I asked him what on earth he was doing and he said, "I'm allergic to the yellow part of the egg not the white." I was very confused by this, he also sad he was allergic to tomatoes but could still eat pizza with sauce on it, apples but only the skins, and some other strange things. I didn't think this was possible at all. Can anyone explain this and tell me if it's even possible to be allergic to one part of an egg and not the other, or is it all in his head. If this is possible, is there an actual name for this condition? The protein composition of the egg white and egg yolk differ appreciably. Hence, it is plausible for one to countenance symptoms of indigestion when consuming the egg yolk as opposed to the albumen, egg whites. It is important to stress that your friend may only an indigestion towards egg yolks as opposed to an immune response to an antigen.
If we consider the protein family, the egg yolk comprises a family of phosvitins, a group of highly phosphorylated proteins capable of mustering iron and calcium metal cations - serving a role in embryo development.
These are primarily absent from the albumen which comprises (with an unexpected name!) a highest percentage of suspended ovalbumin, ovotransferrin and ovomucoid. As demonstrated by the American College of Allergy, Asthma & Immunology, it is feasible to suffer an intolerance towards the egg yolk and yet suffer no gastro-enteric indigestion to the egg whites.
More information regarding the American College is available from: https://acaai.org/allergies/types/food-allergies/types-food-allergy/egg-allergy
The following is multiple choice question (with options) to answer.
Where might you find eggs? | [
"forest",
"space",
"lava",
"ocean"
] | A | an egg requires warmth to develop |
OpenBookQA | OpenBookQA-4560 | cell-biology, gene-expression, development, embryology
I'm reluctant to go into too much detail on this because you're asking about a complex process that is still under active study and I'm unclear as to how much information you actually want. A book could be written on this subject alone, and many review papers have been published. Here's a recent one:
Development: Do Mouse Embryos Play Dice?
I suggest you read that and then if you have further, more specific questions, we can try and answer them for you.
The following is multiple choice question (with options) to answer.
Which is more likely to be able to develop? | [
"an egg under water",
"an egg near a light bulb",
"an egg in the arctic",
"an egg in a freezer"
] | B | an egg requires warmth to develop |
OpenBookQA | OpenBookQA-4561 | thermodynamics, water, freezing
IMHO we now have a pretty decent picture of what is (and isn’t) happening. Remember, the objective is to make an impressive fog. It is exponentially important to have hot water in order to drive a lot of H2O into the vapor phase. It is important to do a decent job of tossing the water, in order to create sufficient surface area for evaporation to occur. It is necessary to have reasonably cold air, to cause recondensation to occur. Extreme cold is not necessary, but doesn’t hurt, and an ice-fog will be more persistent than the other kind of fog.
--- John S. Dunker, 2004, "How to Make Fog"
http://www.av8n.com/physics/ice-fog.htm
I have a few things to add:
In videos of the phenomenon, the cloud forms close to the surface of the liquid, leading to a "telescoping" effect as the water moves through the air.
One possible explanation of this is that the latent heat of freezing released by the water closest to the cold air heats the water further from the cold air. This layer of "inner water", since it is already close to boiling, will evaporate, dispersing the water molecules and quickly freezing, exposing and heating another layer, and so on.
It may seem strange that freezing water would heat surrounding water, but remember that the latent heat of freezing must go somewhere, and liquid water is more conductive than air. That, in addition to the rapid expansion and insulation provided by the water vapor (remember the Leidenfrost effect) is what allows it to disperse so quickly without bonding into a mass of ice.
I don't have enough of a background in atmospheric physics to point to relevant literature, but I hope this provides some insight into the subtleties of the phenomenon.
The following is multiple choice question (with options) to answer.
When droplets freeze as they assail from high above they become | [
"hurricane",
"sleet",
"tornadoes",
"drizzle"
] | B | precipitation is when hail fall from clouds to the ground |
OpenBookQA | OpenBookQA-4562 | everyday-life
Title: Strange pattern on car windows
A couple of days ago I was in a friend's car, and I noticed this pattern on the windows; I took a picture of the sun through the window to make it clearly visible.
The night before had been quite cold, but I don't think that the temperature went below $0$ °C, even though I am sure that it did some days before.
I can speculate that the phenomenon originated from some condensation/freezing of humidity on the outside of the car window, so I searched the web for pictures of water condensation and frost patterns (and also water staining) on car windows, but couldn't find anything similar.
What could be the origin of this intricate pattern? From your question, I can guess that the weather is rainy in your region.
When you drive a car in the rain, the water drops pass your windows at an angle. This, plus wind and other winter stuff causes the path of the drops to twist and jiggle like in this photo
I would also guess that the rain stopped while still driving, so the water could've evaporated in this pattern. The sunlight then makes those residues more pronounced when you took the picture.
Take a look at the following picture from a google search of 'water stains on glass'. To me it looks similar to your photo, just without the effect of moving window (keep in mind that the residues in the water may differ from one place to another due to pollution and etc., so the stains don't have to look the same).
The following is multiple choice question (with options) to answer.
What weather phenomena can crack your windshield? | [
"condensation",
"a gentle breeze",
"clouds",
"ice precipitation"
] | D | precipitation is when hail fall from clouds to the ground |
OpenBookQA | OpenBookQA-4563 | zoology
Capybara, rabbits, hamsters and other related species do not have a complex ruminant digestive system. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft fecal pellets of partially digested food are excreted and generally consumed immediately. Consuming these cecotropes is important for adequate nutritional intake of Vitamin B12. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the feces of their mother to obtain the bacteria required to properly digest vegetation found on the savanna and in the jungle. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to obtain any nutritional value from plants.
Eating garbage and human feces is thought to be one function of dogs during their early domestication, some 12,000 to 15,000 years ago. They served as our first waste management workers, helping to keep the areas around human settlements clean. A study of village dogs in Zimbabwe revealed that feces made up about 25% of the dogs’ overall diet, with human feces making up a large part of that percentage.
Coprophagia
Daily rhythms of food intake and feces reingestion in the degu, an herbivorous Chilean rodent: optimizing digestion through coprophagy
Coprophagia as seen in Thoroughbred Foals
The following is multiple choice question (with options) to answer.
Which is most helpful to a constipated Elephant? | [
"cheese",
"bubblegum",
"oats",
"empty promises"
] | C | plants are a source of fibers |
OpenBookQA | OpenBookQA-4564 | zoology, species-identification, ornithology, behaviour
Title: What is this crow eating, and is it a common part of the corvid diet? Here's a picture (by Rob Curtis) of a crow carrying and eating the corpse of what looks a bit like a small hawk or falcon:
Other pictures clearly show the crow is eating the dead bird. This image shows the underside of the head and beak; this one shows its legs, which are grayish.
What bird is being eaten?
Is this bird a usual part of the corvid diet? Or did the crow just opportunistically scavenge a dead bird? Crows are omnivorous, and will eat almost anything they find or can kill.
In this case the prey looks like a Yellow-Shafted Flicker.
The following is multiple choice question (with options) to answer.
Eagles eat what? | [
"grass",
"whales",
"hoppers",
"apples"
] | C | eagles eat rabbits |
OpenBookQA | OpenBookQA-4565 | reinforcement-learning, ai-design, control-theory
Without any proximity reward, you will rely on the wolf literally bumping into the rabbit through random behaviour, before it will have any data example that getting the vector between itself and the rabbit close to (0,0) is a good thing. You may need to have a relatively large capture radius, plus limit the area that the wolf (and eventually rabbit) can explore, in order to avoid very long sequences of random behaviour where nothing is learned initially.
The following is multiple choice question (with options) to answer.
Which would likely protect a rabbit? | [
"surfing",
"above ground nesting",
"swimming",
"living under ground"
] | D | eagles eat rabbits |
OpenBookQA | OpenBookQA-4566 | Ofcourse, there's other practical things you could do, like using densities, etc. But I think one of the two above would be appropriate, just not sure which.
12. ## Re: Help with conjectures (proof)
the solution to the 3 boxes problem is simple:
all 3 boxes are labelled incorrectly. so take one candy (just one!) from the box labelled "mints and chocolates".
if it is a mint, then it is the box of mints. thus the box labelled "chocolates" cannot be chocolates, nor can it be mints, so it must be the mixed candies, and the box labelled "mints" must be the chocolates.
if, however, it is a chocolate, then box labelled "mints" cannot be mints or chocolates, and thus THAT one must be the mixed candies, and the box labelled "chocolates" must be mints.
EDIT: on the caveat on "h":
have you tried to express 2 as the sum of two primes?
h is a very famous conjecture, known as Goldbach's conjecture. no proof is known, but it is widely regarded as true (it has been computer verified for all integers less than 4 x 1018, according to Wikipedia).
The following is multiple choice question (with options) to answer.
Marshmallows plus ____ technically make a different substance. | [
"steak",
"cookies",
"chocolate",
"fire"
] | D | chemical reactions cause different substances to form |
OpenBookQA | OpenBookQA-4567 | population-genetics
Title: Average and lowest degrees of kinship/consanguinity among humans? I would appreciate insight into the average, median, RMS or any similar measure of relatedness among the current world population - and perhaps something about how rapidly this may be changing. A similar question is how un-related any two humans can be: i.e., what is the lowest degree of consanguinity between the two most distantly related people. The context is an exploration of how humans have evolved tendencies toward racism and other in/outgroup distinctions, when all humans share such a large fraction of DNA with each other, very nearly as much with non-human primates, and about half even with fruit flies. Might be some helpful lessons in there!
Apologies if the question is ill-formed, or answer readily available someplace - I've browsed the Web for several years on this topic, and found nothing I could understand..
Accessible material about most recent common ancestor and identical ancestor point seems to indicate a wide range of both methodologies and results, based mainly on statistical simulations since "hard" genetic structures apparently do not persist. MRCA datings based on mitochondrial and other genetics seem to line up with human behavioral modernity, ca. 200 kya. But there seem to be extreme estimates as recent as 2.3 kya, which implies a lot of mobility and high fertility by some not-so-distant forebears (like Genghis Khan). In any case, IAP may be a better starting point for this shared-anncestry question.
I'm guessing that no human is further than about a 10th~12th cousin to any other. Can't be more that 32nd, since 2^33 is more than the number of living humans!
All thoughts, including guesses more informed than mine, will be appreciated.
~ ~ ~ ~ ~
Addendum - tried to post this as an answer, but it was deleted:
MANY thanks to Zo-Bro-23 for the time, effort and creativity to create his response. I hope it is well-indexed for future explorers to find!
In case useful or interesting to anyone,or sparks further contributions, here were/are my main motivations for this inquiry:
The following is multiple choice question (with options) to answer.
Which number is likely an inherited characteristic of a human? | [
"5 favorite shirts",
"5'10",
"10 dogs",
"15 friends"
] | B | height is an inherited characteristic |
OpenBookQA | OpenBookQA-4568 | newtonian-mechanics, rotational-dynamics, estimation, stability
Title: Human Lean Equation For a medical experiment I am doing, I need an equation to find the angle at which someone will lean before falling. I am not mathematically inclined in terms of advanced stuff, I am more so of a trigonometry person.
I assume factors that will be needed are BMI, including height and weight, but that is really all I have. For example, I am a 5'11" (180.3cm) tall female. I weigh 165 pounds (74.8kg). I want to find out, computationally (because I could measure myself), how far I could lean before I fall.
Any ideas of how I could go upon this? Even though your body is not a simple, homogeneous, rigid object, we can calculate a little... With a lot of assumptions.
I assume, your feet stand next to each other, not in a step-forward-position. And I assume, the question is about leaning forward/backward, not sideways.
And I assume that the arms have to be aligned at the side of the body.
First step, we need to locate your center of gravity (CG). Even if you feel light/heavy hearted, we assume you to be symmetric. We also assume you to be front-back-symmetric, except for your feet.
Now we need the hight-coordinate of CG. You can find it via plancking across a bar. Let's assume your result is that CG is 99cm from floor up.
Next up, we need your shoe size. I guess you at an american women's size of 11.5, which equates to 27cm foot-length.
If you ever took dance classes, you may remember that you were instructed to "put your weight over your heel", or over the center of your feet. Let's assume that this little shift can be done without "leaning".
As you are "more of a trigonometry person", here comes the fun part:
We think of you (having "weight over heel") as a L-shape, with your feet being 27cm, and the stem of the "L" being 99cm (height of CG). Now you gradually lean forward, and when CG passes over your toes, you fall.
The following is multiple choice question (with options) to answer.
You are unable to naturally make yourself taller because height is determined by | [
"parents",
"Cookies",
"Space",
"Eggshells"
] | A | height is an inherited characteristic |
OpenBookQA | OpenBookQA-4569 | climate-change, climatology
Thus, your question is a little misconstrued: we can't answer "Who are the 3%?" because the 3% are research articles rather than people. However, we can ask "Which are the 3% of published research abstracts which do not support the scientific consensus?" And since Cook et al. (2013) is an open access paper with supporting data provided, you can easily answer this question for yourself: simply download the data file from the supplementary data page and look at the papers with an endorsement rating of 5, 6, or 7. (It's in CSV format, so is easy to load into a spreadsheet or text editor.) Further supplementary data is available from the project page at Skeptical Science, and replication of the research is actively encouraged. If you're interested in the actual people behind the 3% of "non-consensus" papers you can look at the author lists for those publications (though of course there's no guarantee that all those authors would still stand by all their conclusions).
I suggest that you start your investigations by reading the paper itself. It's clear and concise, and will give you much more thorough information about the methodology and supporting data than I've been able to fit into this answer.
The following is multiple choice question (with options) to answer.
Which would an ecologically minded individual most support? | [
"windmills",
"oil",
"fracking",
"gas"
] | A | a windmill converts wind energy into electricity |
OpenBookQA | OpenBookQA-4570 | atmosphere, ocean, hydrology, climate-change
Comment: I strongly endorse the use of wind and hydropower as sources of energy over the further use of fossil fuels. However, I still think it is important to do research into the actual renewability of presumed-renewable energy sources, as we don't want to end up with another fossil fuel-type situation, in which we become aware of dependency on these energy sources and their malignant environmental side-effects long after widespread enthusiastic adoption. Electricity from waves, from hydro (both run-of-river and storage) and from wind, are all indirect forms of solar power. Electricity from tides is different, and we can deal with that in a separate question. Global tidal electricity generation is not yet at the scale of gigawatts, so it's tiny for now.
Winds come about from the sun heating different parts of the planet at different rates, due to insolation angles, varying cloud cover, varying surface reflectivity, and varying specific heat of surface materials. Temperature differentials create wind currents.
Waves come about from wind, so they're a twice-indirect form of solar power.
Sunlight on water speeds up evaporation, lifting the water vapour into clouds, giving them lots of gravitational potential. That rain then falls, sometimes onto high land, from where it can be gathered into storage reservoirs that are tapped for electricity, or where it flows into rivers that are then harnessed in run-of-river hydro.
How much power is there? Well, the insolation from the sun is, at the outer boundary of the Earth's atmosphere, at an intensity of about 1400 Watts per square metre. The Earth's albedo is roughly about 30% - i.e. on average about 400 Watts are reflected back into space, giving an average irradiation into the Earth of about 1000 Watts per square metre. Picture the Earth's surface as seen from the Sun: wherever the Earth is in its orbit on its own axis, and around the Sun, the Sun sees a disc that has the Earth's diameter, so the surface area exposed to the Sun is just $\pi$ times the square of Earth's radius, which is about 6 300 kilometres.
So the incoming solar radiation is $1000 \times 6,300,000^2 \times \pi \approx 125 \times 10^{15} \rm \ W$
The following is multiple choice question (with options) to answer.
There is a growing movement to harness the power of wind in order to | [
"power rangers",
"nothing",
"heat our homes",
"eat cookies"
] | C | a windmill converts wind energy into electricity |
OpenBookQA | OpenBookQA-4571 | botany, color
Hypothesis 1
It should be remembered that chlorophyll is far from being the only pigment found in leaves. For example, carotenoids - which give yellow and reddish colors - are present in plant leaves. There are many carotenoids (according to Wikipedia there are over 1100 known, but that number will continue to grow). The biological roles of these carotenoids are also varied. In the course of the question, we may be interested, for example, in the photoprotective role of carotenoids. They are involved in the deactivation of reactive oxygen species (ROS). ROS can be formed during photosynthesis and can potentially be harmful to cells. Therefore, in conditions of excess solar radiation, plants can increase concentrations of carotenoids to prevent oxidative stress. It has already been pointed out to you in the comments that younger leaves look yellow - this is a common occurrence. The leaf is a very expensive organ, in the sense that the plant invests a lot of plastic substances in its development. So it makes sense that young, growing leaves get extra protection. That is, a young leaf that has not yet formed all the necessary structures (thick enough cuticle, efficient conductive system, etc.) is less efficient in terms of photosynthesis and therefore more susceptible to negative processes of photodamage. Increased concentrations of carotenoids, among other things, can reduce such risks. If you add to this the small thickness, it is understandable why young leaves often look more yellow.
Hypothesis 2
I have already said that leaves are expensive organs. They have a high protein content, which is very valuable to the plant. If a leaf is damaged or aged, there is a threat of irreversible loss of protein, which would be a great waste. Therefore, in such cases, plants trigger complex processes of removing valuable substances from the leaves. In particular, chlorophyll begins to break down, and the decomposition products are transported to the more durable parts of the plant. This is the reason why leaves change color in the fall, before defoliation. When the concentration of chlorophyll decreases, other pigments, such as carotenoids, increasingly affect leaf color. That's why damaged and old leaves often turn yellowish.
Although, I doubt that in the case of your plant, this process is often the cause for yellow leaves.
Hypothesis 3
The following is multiple choice question (with options) to answer.
Older plants will most-likely have more leaves than when | [
"they were babies",
"Seventeen",
"Hot dogs",
"botany"
] | A | when a plant grows , the number of the leaves of that plant may increase |
OpenBookQA | OpenBookQA-4572 | If the papillae (bumps on your tongue) can sense 5 basic tastes
and any combination of those tastes produce a unique taste,
how many possible unique tastes can you have?
. . $\displaystyle \begin{array}{ccccc} \text{1-at-a-time:} & _5C_1 &=& 5 \\ \text{2-at-a-time:} & _5C_2 &=& 10 \\ \text{3-at-a-time:} & _5C_3 &=& 10 \\ \text{4-at-a-time:} & _5C_4 &=& 5 \\ \text{5-at-a-time:} & _5C_5 &=& 1 \\ \hline & \text{Total:} && {\color{blue}31} \end{array}$
Call the five basic tastes: $\displaystyle a,b,c,d,e$
You can list them and count them yourself . . .
. . $\displaystyle \begin{array}{ccc}\text{1-at-a-time:} & a,b,c,d,e \\ \\ \text{2-at-a-time:} & ab,ac,ad,ae,bc\\ & bd,be,cd, ce, de \\ \\ \text{3-at-a-time:} & abc, abd, abe, acd, ace \\ & ade, bcd, bce, bde, cde \\ \\ \text{4-at-a-time:} & abcd, abce, abde, acde, bcde \\ \\ \text{5-at-a-time:} & abcde \end{array}$
6. Originally Posted by Soroban
Hello, Masterthief1324!
I agree with skeeter and Dinkydoe . . .
The following is multiple choice question (with options) to answer.
What would you likely notice the taste of? | [
"ice",
"tropical twist",
"water",
"air"
] | B | animals taste flavors |
OpenBookQA | OpenBookQA-4573 | If the papillae (bumps on your tongue) can sense 5 basic tastes
and any combination of those tastes produce a unique taste,
how many possible unique tastes can you have?
. . $\displaystyle \begin{array}{ccccc} \text{1-at-a-time:} & _5C_1 &=& 5 \\ \text{2-at-a-time:} & _5C_2 &=& 10 \\ \text{3-at-a-time:} & _5C_3 &=& 10 \\ \text{4-at-a-time:} & _5C_4 &=& 5 \\ \text{5-at-a-time:} & _5C_5 &=& 1 \\ \hline & \text{Total:} && {\color{blue}31} \end{array}$
Call the five basic tastes: $\displaystyle a,b,c,d,e$
You can list them and count them yourself . . .
. . $\displaystyle \begin{array}{ccc}\text{1-at-a-time:} & a,b,c,d,e \\ \\ \text{2-at-a-time:} & ab,ac,ad,ae,bc\\ & bd,be,cd, ce, de \\ \\ \text{3-at-a-time:} & abc, abd, abe, acd, ace \\ & ade, bcd, bce, bde, cde \\ \\ \text{4-at-a-time:} & abcd, abce, abde, acde, bcde \\ \\ \text{5-at-a-time:} & abcde \end{array}$
6. Originally Posted by Soroban
Hello, Masterthief1324!
I agree with skeeter and Dinkydoe . . .
The following is multiple choice question (with options) to answer.
What tastes flavors? | [
"flamingos",
"metals",
"stars",
"bicycles"
] | A | animals taste flavors |
OpenBookQA | OpenBookQA-4574 | newtonian-mechanics, energy-conservation, momentum, conservation-laws
So the answer is that regardless of the current motion of $M$ it is always possible to shoot $m$ at $M$ such that it transfers all its kinetic energy to $M$ and thus the maximum amount is 100%.
The following is multiple choice question (with options) to answer.
Which likely has the highest force exerted upon it? | [
"the palm of your hand",
"a pillow for sleeping",
"a home run baseball",
"a button on a keyboard"
] | C | as force exerted on an object increases , distance travelled will increase |
OpenBookQA | OpenBookQA-4575 | the-sun, dwarf-planets
Title: What would the sun look like from aphelion of The Goblin's orbit? I was amazed to find out about the discovery of The Goblin 2015 TG387 with an orbital period of more than 32 thousand years and a aphelion of more than 1955 AU! That is an astonishing distance. What would the sun look like from aphelion on The Goblin? Could a naked eye observer distinguish it from the rest of the sky? Yes, easily.
1955 AU is a long way, but it is only 0.03 of a light year. The sun would still be less than 1/100 of the distance to the next star.
The brightness of the sun would be much less: about 4000000 times less bright, but that is about 16 magnitudes. The sun from Earth is -27 magnitude, so the sun would appear as a magnitude -10 star. It would be much brighter than any other star, and would easily outshine Venus as seen from Earth. In fact it would be 100 times brighter than Venus. It would be as bright as a half-moon (strong enough to cast shadows, but not to read by)
The following is multiple choice question (with options) to answer.
A yellow dwarf is an origin of | [
"cold",
"sound",
"life",
"heat"
] | D | a hot something is a source of heat |
OpenBookQA | OpenBookQA-4576 | evolution, psychology, sociobiology
Title: Female preference for males who are already in a relationship A common saying is that women are generally more attracted towards men who are already in a relationship, and this phenomena does seem to have its own place in popular culture that is not matched by a corresponding male preference for women who are already in a relationship.
From an intuitive viewpoint I think it would make sense from the woman's viewpoint in an system of information economics where the fact that a male is engaged in a successful relationship with another female, or several other females, might provide extra and positive information about the evolutionary value of the male.
But how about the possibility for a male to use the same trick?
Is there any empirical evidence for this behaviour at all either in humans or in other species, or is this just a cultural artefact in some human societies? If there is empirical support, is there a consensus on the plausible evolutionary pathways involved here? This is a widely researched topic in the overlap between social sciences and evolutionary biology. Evolution has become very influential in understanding human interaction and preferences.
This chapter from "The Adapted Mind : Evolutionary Psychology and the Generation of Culture" will give you an idea of how all this plays out in the big picture - its a fairly comprehensive review of many factors considered in human mate choice. The study may be psychological, but the logic is derived from biology these days. (stackexchange won't let me link to google books - you can search for the title and look at chapter 6).
Evolutionary tendencies will favor more successful offspring. But for people it includes not only the genetic qualities of the mate (appearance, height, disease resistance, health) but also social qualities (how reliable or willing a mate is to support offspring).
First off you can see that there are many many factors which women take into consideration in their preferences. Its commonly said they are more complex than men, but that's another question. You have to take a range of factors holistically including the social environment.
I can't find this particular issue addressed in the literature, but I think that it might be attractive to women in some social settings. If there is a lot competition for 'quality' mates or resources for instance - if you have very few secure males or pessimistic females might create pressure which would cause females to prefer males which were successful.
The following is multiple choice question (with options) to answer.
Which likely most relies on its looks to reproduce? | [
"the shark",
"the horse",
"the spider",
"the peacock"
] | D | coloration is used to find a mate by some animals |
OpenBookQA | OpenBookQA-4577 | air-pollution
Title: Less pollution: moving hurricane debris to other regions for use, or burning? When a big hurricane hits, it can create debris on the scale of $\mathrm{10^8 yd^3}$. Cities in Florida, Texas, and other affected areas are struggling to hire enough trucks and drivers to pick it up quickly. But aside from that, I noticed many of the areas have started to burn the debris once it starts building up.
Got to wondering... typically mulch comes in modestly pricey, and when free mulch is offered, it often goes quickly.
So assuming a fair portion of debris is mulchable and is of interest to other areas, and that we can acquire typical transportation resources, then we'll set up transfer from collection sites to those other regions rather than burning it. What would be the net pollution result?
If removed for mulch and such: trucking pollution + decomposition (- trees saved locally??)
If burned: the burning pollution.
Obviously it's about approximation rather than exacts, it's probably hard to appraise the different byproducts from burning versus decomposition, and a lot probably depends upon the way it is burned. But as a whole, can we get a rough estimate of comparable quantities/damage done... is it less pollution/damage even to truck it an average of 3000 miles? 1000 miles? 100 miles? 10 miles? Should it be burned on the spot (if done safely)? Would think there's got to be some way to get a very rough idea.
Certainly the best option if viable might be leaving it in place to decompose. But considering how upset people are getting at having debris around these parts a month later, exclude that option from the possibilities.
Trucking or burning, how do they compare? As the question was changed, my answer attempts to evaluate only the difference between burning and transporting. Please correct my values if my quickly found sources are inaccurate or you find more representing. I know there is quite a few unwritten assumptions that simplify this problem.
The following is multiple choice question (with options) to answer.
Landfills can cause | [
"noise pollution",
"overpopulation",
"overgrowth of grass",
"bad odors"
] | D | an landfill is a source of pollution |
OpenBookQA | OpenBookQA-4578 | combustion
But when things are that hot, plenty of other reactions can occur and this is particularly noticeable if the thing that is burning is less pure than charcoal (which is mostly carbon). Raw coal, for example, contains a lot of volatile impurities (smokeless coal is deliberately treated to reduce the volatile impurities). When the primary reaction of burning carbon happens in raw coal, those volatiles are often turned to gases and driven off the coal to combust as gases far from the solid coal. Of course this is happening at the same time as solid carbon in the coal is burning so the two effects are mixed up to give both glowing coal and gases burning some distance from the glowing coal. Old home chemistry sets used to contain experiments that allowed these effects to be separated. Raw coal is placed in a vessel connected to a tube allowing any emerging gas to be directed far away from the coal. The coal is heated with an external source (eg a Bunsen burner). The emerging volatile gases can then be lit without setting the coal on fire giving a flame a long distance away from the heated coal.
The same can be done with wood (which contains even more volatile and flammable components than coal).
So, when wood or coal burn in an uncontrolled way both the burning of the solid and the burning of the volatiles contained with the solid occur at the same time but the volatiles (as gases) can move far from the solids before they burn. This is why the position of the fame can be far from the burning solid.
Also worth noting
In addition to the volatiles being driven from the burning solid, partial combustion can also create gases like carbon monoxide which can then travel some distance away from the solids while burning (though CO tends to have not very bright blue flame). In fact a controlled version of this reaction (which sometimes also used steam to create hydrogen) was once the primary way of creating town gas (which was widely distributed to support gas lighting and cookers in cities.
If the primary goal is to create flames designed to illuminate rather than heat then burning can be designed to create a lot of small hydrocarbon particles in the flame. This is intentional for things like candles. Here the heat may come from burning the was but the light comes because that burning creates small incandescent soot particles which are heated enough to glow turning a lot of the energy into light.
The following is multiple choice question (with options) to answer.
A cast iron stove uses what as fuel | [
"lasers",
"timber",
"light",
"sound"
] | B | a stove generates heat for cooking usually |
OpenBookQA | OpenBookQA-4579 | photosynthesis, respiration, ecosystem, decomposition
Maybe you should study the metabolic processes of plants and life in general to better understand this. All life consists of chemical reactions that build up structures; in order to build them up you need energy (because of the second law of thermodynamics), and all living things create that energy by breaking down complex molecules into simpler ones. (as such it would be more accurate to say that all life consists of chemical reactions that build up and break down various structures). You might be wondering "but what about the difference between autotrophs and heterotrophs I heard about"; the difference between those is where they get the complex molecules from in the first place. Autotrophs use a different source of energy to build them up while heterotrophs get them from their environment. As such, you can think of every living thing as being made of two kind of molecules: those that actually form their structure (in humans, the molecules that make up cell membranes, bones, muscles, etc) and those that are stored in order to be broken down to power the whole system (in humans that's fat, glycogen, glucose, etc). Of course a molecule can do both; if you're starving your body may start to break down structural molecules for power. There are many different ways of breaking down those big molecules for power; the most efficient one, that starts with a big chain of carbon atoms and cuts it down into individual CO2 molecules using O2 molecules, is called aerobic respiration (i.e. respiration that uses oxygen).
Because those complex molecules are required to power all life, autotrophs (the organisms that actually make them) are very important, and the processes they use to make them are very important too. The process that makes almost all of the molecules that power almost all life on earth is photosynthesis, which uses the energy from the sun to power a reaction that converts CO2 from the atmosphere into big carbon-based molecules we'll call carbohydrates. This is called "fixing carbon", since the carbon atom is the most important one; measuring how much photosynthesis is happening is another way of measuring how many carbon atoms move from being part of a CO2 molecule to being part of a plant.
The following is multiple choice question (with options) to answer.
When a vegetative organism lifeform goes into a state of creating a life from itself, what is it called? | [
"dispersing reproduction units",
"painting",
"seed harvest",
"hibernation"
] | A | seed dispersal has a positive impact on a plant |
OpenBookQA | OpenBookQA-4580 | ecology, behaviour, sociality, predation, community-ecology
Title: How selective are wolves about the size of their prey? For an animal that lives and hunts socially like a wolf, is there a lower threshold to the size of prey items they will hunt? A pack wouldn't have much trouble with catching say a rabbit, but would the food provided be enough to actually make the hunt worthwhile? What is the limit in which a prey item becomes too small to be worth catching? You should not post here until you've demonstrated your own research effort. Given this stipulation -- and the rich literature about this very topic -- I will keep my answer cursory so as to act as starting points for your search. A simple Google or google Scholar search on your part will reveal many more details/studies.
You should review the following ecological concepts: prey switching, optimal foraging theory, principle of allocation, and others.
Some accessible articles on Prey-to-predator-size ratio include: Henriques et al. 2021, Tsai et al 2016, Cohen et al 1993, and Vézina 1985
Regarding wolves:
According to Becker et al 2018:
[Wolf] Prey selection is influenced by the absolute and relative abundances of prey types, the life history characteristics of predators and prey, and the attributes of the environment in which these interactions occur.
Smith et al. 2010 demonstrate that diets vary with season -- their focus being on winter diets.
Huggard 1993 shows the impact of environmental variables such as snow.
Herd density plays a significant role:
Sand et al. 2016
Davis et al 2012 showed that lower density of secondary prey mattered more than heightened density of primary prey.
Huggard 1993 (Canadian Journal of Zoology) showed that density of herds (vs herd density) mattered more in Banff National Park in Canada. Herd size and habitat also mattered -- with wolves avoiding some habitats and seemingly choosing places that optimized preferred habitats and large herd size.
Wolf scat/diet studies showing smallest species in their diet:
Sin et al 2019: smallest for Sandanavian wolves = domestic dogs
Nowak et al 2011 showed the following small prey made up the stated percentages of wolve's diets in Poland:
brown hare Lepus europeus (2.5%) and Eurasian beaver Castor fiber (1.4%). Domestic animals, exclusively dogs and cats, made up 1.0% of food biomass.
Works cited:
The following is multiple choice question (with options) to answer.
Ligers are less likely to thrive when there is | [
"massive antelope herds",
"famine",
"abundant food",
"readily available prey"
] | B | an animal being born when food is available has a positive impact on that animal 's health |
OpenBookQA | OpenBookQA-4581 | photosynthesis, chloroplasts
Title: Chloroplasts in an animal cell What would happen if we inject a chloroplast organelle into an animal cell?
Will the animal cell destroy it? Or is it possible that the chloroplast will somehow survive, and even replicate? Could there be photosynthesis in such a cell, or will some of the necessary mechanisms be missing? To answer your bigger question:
Yes, most of this is possible - under some conditions -, and animals and animal cells can acquire chloroplasts, and use them.
E.g.: see Elysia chlorotica whose cells actively take up chloroplasts and use them, and keep them alive (though not replicating). - Though some genes of algae are also contained in the Elysia chlorotica genome - which may be considered as partial replication.
Also there are salamanders that have replicating algae within them (since embryogenesis) - even algae (with chloroplasts) within animal cells - though here the algae might be rather understood as symbionts or "cell types", and the animal cells don't have the chloroplasts by themselves.
The following is multiple choice question (with options) to answer.
All of the following contain chloroplasts but this | [
"rose bushes",
"sea anemones",
"seaweed",
"algae"
] | B | a plant cell contains chloroplasts |
OpenBookQA | OpenBookQA-4582 | entomology
Title: What is the name of this tiny creature? It looks like a tiny piece of moving cotton? By chance, I saw this tiny insect on my bag a few days ago in Sydney. Am I the first person who has pinpointed this animal?! If not can you please let me know its name? From your image, it looks like it might be a woolly aphid. I just did a bit of cursory research, and it looks like they're often described as floating pieces of fluff, that seem to wander instead of directly heading somewhere. The fluff on their back is actually wax produced as a defense mechanism from predators and the like. I hope this is what you were looking for!
The following is multiple choice question (with options) to answer.
A squirrel likely | [
"stores food for the summer",
"stores food for upcoming harsh conditions",
"has little need to store food",
"stores food for the spring"
] | B | if an animal relies on plants for food then that animal must store enough food to last through the winter |
OpenBookQA | OpenBookQA-4583 | python, beginner, game, functional-programming, adventure-game
winter = '\n' + '''29 January 2029. It is five weeks into winter and the season shows no mercy. A drought happened for a majority of the last fall and it devastated
the food supply. As your community dives deeper into the winter, you realize that your supply will run out if consumption is not altered. You could do one of two options: reduce
consumption among civilians, or ignore the risk and take a chance([ALTER SUPPLY]X} {B[IGNORE RISK]).''' + '\n> '
alter_supply = '\n' + '''Your government is now seen as selfish. You took the risk to protect the important people and "do your best with the rest". You have suffered heavy
civilian losses but your army and government losses have been few. As a result, there is division and danger in the streets. Riots breaking out, murders, arson, all happening in
your community.''' + civil_great_decrease
ignore_risk = '\n' + '''Your community did better than expected during the period. That is until you ran out of food in early March. Now you rely solely on scavenging,
risking getting devoured by zombies in order to go another day. Half your community is either dead or lost with great amount of casualties from civilians and
non-civilians.''' + army_great_decrease
The following is multiple choice question (with options) to answer.
Herbivores need to stock up on food before winter because | [
"plants will burn",
"plants will fly",
"plants will perish",
"Plants will cry"
] | C | if an animal relies on plants for food then that animal must store enough food to last through the winter |
OpenBookQA | OpenBookQA-4584 | entomology
Title: Constantly wiggling moth pupa - will it emerge soon? Today I found a moth pupa in the soil in my garden in western Sweden. It's about 15 mm long.
I have found similar ones before, but this one is wiggling a lot more, even after I put it down and put a bit of dirt over it. It's been moving for more than an hour now, but less now than in the beginning.
I was hoping to see it emerge, but if it will take more than a day or so, I will probably put it back. So, what I'm wondering is if this wiggling is any indication of how soon it will emerge. Or if there are other ways to tell.
Update: an hour later it has stopped moving. Maybe it was just very disturbed by my presence. I'm keeping it in a jar with soil and a stick for climbing up on, and I'll decide what to do with it tomorrow.
Update: 12 hours later and it seems very still. But I'm letting the question remain since I really want to know if there are any signs to look for.
Final update: After 16 days it had turned almost black, and was still very active when handled.
And after 17 days this moth came out: I posted the same question on tumblr and got an answer:
It depends on the species. This one looks like a Noctuid. I’d give it
two weeks to a month or so. You may be able to see its wings showing
through the darkening pupal case when the time draws near! Just make
sure you give it somewhere to climb up and expand its wings when it
ecloses.
After keeping it until the moth emerged, I now know that wiggliness is not an indication of maturity, but turning dark is.
The following is multiple choice question (with options) to answer.
Metamorphosis is complete at | [
"adulthood",
"embryo",
"hatching egg",
"larva"
] | A | a moth undergoes metamorphosis |
OpenBookQA | OpenBookQA-4585 | entomology
Title: Constantly wiggling moth pupa - will it emerge soon? Today I found a moth pupa in the soil in my garden in western Sweden. It's about 15 mm long.
I have found similar ones before, but this one is wiggling a lot more, even after I put it down and put a bit of dirt over it. It's been moving for more than an hour now, but less now than in the beginning.
I was hoping to see it emerge, but if it will take more than a day or so, I will probably put it back. So, what I'm wondering is if this wiggling is any indication of how soon it will emerge. Or if there are other ways to tell.
Update: an hour later it has stopped moving. Maybe it was just very disturbed by my presence. I'm keeping it in a jar with soil and a stick for climbing up on, and I'll decide what to do with it tomorrow.
Update: 12 hours later and it seems very still. But I'm letting the question remain since I really want to know if there are any signs to look for.
Final update: After 16 days it had turned almost black, and was still very active when handled.
And after 17 days this moth came out: I posted the same question on tumblr and got an answer:
It depends on the species. This one looks like a Noctuid. I’d give it
two weeks to a month or so. You may be able to see its wings showing
through the darkening pupal case when the time draws near! Just make
sure you give it somewhere to climb up and expand its wings when it
ecloses.
After keeping it until the moth emerged, I now know that wiggliness is not an indication of maturity, but turning dark is.
The following is multiple choice question (with options) to answer.
A moth undergoes what? | [
"migration",
"stage conversion",
"amelioration",
"surgery"
] | B | a moth undergoes metamorphosis |
OpenBookQA | OpenBookQA-4586 | dna, human-genetics, dna-sequencing, genomics
Title: Is it possible to deduce facts about a person's parents just by studying his/her genome? As an example, suppose Anne had abusive parents. Is it theoretically possible to deduce this from her genome even if she didn't inherit this quality (of being an abusive parent)? It might seem pernickety but you often can't deduce from a genome; you can only infer from it. For many characteristics about a person, there are only rough, probabilistic associations between genotype and phenotype. Not one-to-one relationships.
You can take an educated guess that someone with a certain genotype could be a social person of European ethnicity with a low risk of psychosis, which might suggest things about their parents. But there are likely many genes that influence those characteristics and still more non-genetic factors. So you couldn't be certain.
For a factor like whether the persons parents had abusive personalities, I think the genetic differences would be so subtle (if existent) and there would be so many other factors (such as the habits and choices of the parents) that you would be very unlikely to be able to draw any conclusive associations. Articles and studies about linking human genetics with a person's characteristics are listed below. If any of the genes in question are linked with those characteristics then the parents of someone with the gene could possibly have those genes and characteristics too.
Personality types including belligerence, charisma, cynicism, housekeeping, lack of personality, obsessive-compulsive behaviour and gullibility.
Psychosis and Schizophrenia risks.
Ethnicity and European ethnicity, which in turn correlate with geographical location, language and certain phenotypes.
Height.
If anyone would like to suggest additions to that list, I'll happily add them.
The following is multiple choice question (with options) to answer.
Parents genes will determine the rabbits | [
"mate",
"food preferences",
"fur color",
"habitat location"
] | C | the coloration of fur is an inherited characteristic |
OpenBookQA | OpenBookQA-4587 | dna, mammals, eggs
Title: In what circumstances does a mammalian egg copy its DNA? In the 2nd episode of the new Cosmos series, the host Neil deGrasse Tyson shows how the white-furred bear could have evolved (reasonable scientific speculation, of course).
If you haven't seen that episode, here's the link. Great show, by the way.
So, it shows the bears eggs, and then goes on to show how there can happen an error in the DNA copying, that leads to the brown pigment production malfunction. Here's an excerpt from the subtitles text:
- great bears roamed the frozen wastes of Ireland.
- This might look like an ordinary bear,
- but something extraordinary is happening inside her.
- Something that will give rise to a new species.
- In order to see it, we'll need to descend down to a much smaller scale, to the cellular level, so that we can explore the bear's reproductive system.
..
- Those are some of her eggs.
- To see what's going on in one of them,
- we'll have to get even smaller.
- We'll have to shrink down to the molecular level.
..
- When a living cell divides in two,
- each one takes away with it a complete copy of the DNA.
- A specialized protein proofreads to make sure
- that only the right letters are accepted
- so that the DNA is accurately copied.
- But nobody's perfect.
- Occasionally, a proofreading error slips through,
- making a small, random change in the genetic instructions.
- A mutation has occurred in the bear's egg cell.
- A random event as tiny as this one can have consequences on a far grander scale.
- That mutation altered the gene that controls fur color.
- It will affect the production of dark pigment in the fur
- of the bear's offspring.
The following is multiple choice question (with options) to answer.
A baby bear has golden fur which is medium length. The reason for this is most likely | [
"gene contributors shared that characteristic",
"its parents are polar bears",
"mother bear has blue eyes",
"parents all have black fur"
] | A | the coloration of fur is an inherited characteristic |
OpenBookQA | OpenBookQA-4588 | mammals, sex-chromosome, gender
Possibly it is just because they choose males that are more likely to have more Y spermatozoa than X
Yes, this is possible. But considering cryptic female choice we may say the same for males. Some of them may seek those females who are more likely to get pregnant with particular sex spermatozoon.
Answering by my own since only now I occasionally came across with "Cryptic female choice" article.
The following is multiple choice question (with options) to answer.
Which would likely reproduce? | [
"copiers",
"waterfowl",
"rocks",
"rivers"
] | B | An example of reproduction is laying eggs |
OpenBookQA | OpenBookQA-4589 | thermodynamics, visible-light, temperature, thermal-radiation, biology
Title: Why are people dark skinned in hotter areas despite dark colour absorbing the most heat? I’m not sure if the reason is in the field of biology or more towards physics but as my reasoning is based on the physics part being that perfectly black bodies are perfect absorbers of heat and light while white is a perfect reflector but we have darker skinned humans near equator and lighter skinned people (as well as animals like polar bears) near the poles, I’ve posted it on physics stackexchange. Also, if the answer is based on the biology of animals and this should belong to biology stack exchange, feel free to let me know. This is a bio question.
The biggest threat to fitness is not lack of cooling, but damage from UV rays. A pigment in black (actually all skin to differing degrees) absorbs the UV so that skin cells don't.
Fair skinned people, from higher latitudes, have another risk to their fitness which is a lack of vitamin D which is produced by the skin when exposed to UV.
As a result of this, fair skinned people in the tropics get more skin cancer than otherwise, and dark people are more likely to have a vitamin D deficiency if far from the tropics.
The following is multiple choice question (with options) to answer.
What's above the muscles and needs direct sunlight | [
"your hide",
"the heart",
"the pancreas",
"the liver"
] | A | the skin is the largest organ in the human body |
OpenBookQA | OpenBookQA-4590 | organs, lifespan
Title: Organs lifespan out of the body What organ can be conserved outside of the body for the longest time and still function when reimplanted? Depends what you consider an organ. Typically though it's the cells which require the most metabolic activity which have the shortest life span. The kidney is the most of the major internal organs with up to 36 hours with liver coming second at up to 16 hours.
The following is multiple choice question (with options) to answer.
The largest organ of the human body is what? | [
"heart",
"brain",
"lungs",
"outer layer"
] | D | the skin is the largest organ in the human body |
OpenBookQA | OpenBookQA-4591 | zoology, ornithology
Bancroft, G. T., & Woolfenden, G. E. (1982). The molt of scrub jays and blue jays in Florida. Ornithological Monographs, (29), iii-51.
Conant, S. (1972). Visual and acoustic communication in the blue jay, Cyanocitta cristata (Aves, Corvidae). The University of Oklahoma.
Dwight, J. (1900). The sequence of plumages and moults of the passerine birds of New York. New York Academy of Sciences.
The following is multiple choice question (with options) to answer.
Bluebirds are found in | [
"vast green fields",
"glaciers",
"volcanic craters",
"ocean waves"
] | A | bluebirds live in grassy spaces |
OpenBookQA | OpenBookQA-4592 | energy-efficiency, thermal-insulation
greater if the window is bigger
less as temperature difference get smaller
Radiative heat transfer
The main factor that is of consideration here is the solar radiation. There are three types of radiation:
Direct radiation: the direct rays of the sun. (this is zero on a cloudy day).
Diffuse radiation: this is always present and its an effect of the presence of atmosphere. In higher latitudes it tends to increase because the sun rays need to "pass through" more atmosphere.
reflected (you can neglect this)
If you can get the rays of the sun (direct radiation) into the house, this will always be a significant plus in the heat balance of the house.
Final thoughts
This problem is very instance specific depending on:
the location of the house
orientation of windows
type of blinds, etc.
Therefore, it is impossible to draw a generic conclusion. As such, only trends can be realistically observed.
At a temperature difference of 30$[^oC]$ it makes sense to close the blinds on a cloudy day. However, if you get closer to 15$[^oC]$ then the savings are diminished.
If the windows are positioned in the right angle and light shines into the room, then expect the added solar radiation will improve the heat balance in favour of open blinds.
The following is multiple choice question (with options) to answer.
More sunlight will be absorbed by | [
"a daffodil with curled leaves",
"a rose with tiny leaves",
"a peony with wide, smooth leaves",
"a daisy with thin, short leaves"
] | C | if something is in the sunlight then that something will absorb solar energy |
OpenBookQA | OpenBookQA-4593 | quantum-mechanics, quantum-information, superposition
When the compass needle points north, that is like a qubit being in the state $\lvert 0\rangle$, and when the compass needle points east, that is like a qubit being in the state $\lvert 1\rangle$. But a compass needle can also point northeast. The direction northeast is neither north nor east, but it is a superposition of equal parts north and east: if you add a north-pointing vector and an east-pointing vector of equal magnitude, you will get a vector that points northeast. Similarly, the qubit state $\frac{1}{\sqrt{2}}(\lvert 0\rangle + \lvert 1\rangle)$ is neither $\lvert 0\rangle$ nor $\lvert 1\rangle$, but it is a superposition of equal parts $\lvert 0\rangle$ and $\lvert 1\rangle$.
The following is multiple choice question (with options) to answer.
Jenny was outside facing her house holding a compass. The needle of the compass was facing her house. Staying in one place she turned around and around, stopping several times. She noticed that whichever way she faced | [
"the compass's needle was facing straight ahead",
"the compass's needle was facing the house",
"the compass's needle was facing her back",
"the compass's needle was facing the west"
] | B | the floating arrow on a compass always points towards the north |
OpenBookQA | OpenBookQA-4594 | thermodynamics, temperature, everyday-life, thermal-conductivity
Title: Why does the temperature of water stay steady at 80 degrees Celsius when heated? A water is being heated in a glass beaker. Although the supply of energy is constant eventually the temperature becomes steady at 80 degrees Celsius. Why is that considering that phase change doesn't happen until 100 degrees Celsius? The temperature of the water becomes constant when the rate of heat loss due to cooling by the environment is equal to the rate at which heat is being supplied by the heater.
The rate of heat loss due to cooling will be approximately described by Newton's law of cooling:
$$\frac{dQ}{dT} = -k(T - T_0) $$
where $T$ is the temperature of the water and $T_0$ is the temperature of the environment.
The following is multiple choice question (with options) to answer.
Above 100 degrees Celsius a kind of water is what? | [
"vapor particles",
"solid",
"ice",
"frigid"
] | A | steam is a kind of water above 100 degrees celsius |
OpenBookQA | OpenBookQA-4595 | electrostatics, electric-circuits, electricity, electric-current, charge-carrier
Title: Potential difference between two hollow spheres and amount of current flow If two Hollow Spheres with radius $r_1$ and $r_2$ have charge $q_1$ and $-q_2$ in them respectively(charges are evenly distributed in the surfaces).The spheres are separated by a distance d .Now We connect a conducting wire from one sphere to another.Then What will be the potential difference between the two ends of that wire and what will be the amount of current flow if the resistance is R in that wire(lets assume the amount of charges in each sphere always remain constant i.e. $q_1$ and $-q_2$)? Can we evaluate these things mathematically i.e. without using the voltmeter or ammeter?
Like, i was thinking of using $\frac{kq}{r} $ formula for calculating the potential at each end and then $V_A-V_B=IR$ to Calculate the amount of Current flow.Is that a right approach? The potential difference
Finding the potential difference is a bit more complicated than you suggested, if I interpreted the meaning of $k$, $q$ and $r$ in your formula correctly.
Before connecting the spheres, they effectively form a capacitor with some capacitance $C$. If $r_1 = r_2$, you can use a formula from wikipedia to calculate $C$, which then gives you the voltage (potential difference) as
$$
V = \frac 1C \frac{q_1+q_2}{2}~.
$$
If $r_1 \neq r_2$, you will have to solve the Poisson equation,
$$
\Delta \phi(\vec r) = - \frac{\rho(\vec r)}{\varepsilon_0}~,
$$
The following is multiple choice question (with options) to answer.
if one electrical conductor contacts another electrical conductor then what will flow through both conductors? | [
"plants",
"air",
"wind",
"zapping power"
] | D | if one electrical conductor contacts another electrical conductor then electricity will flow through both conductors |
OpenBookQA | OpenBookQA-4596 | atmospheric-science, meteorology
Title: Why would El Niño affect atmospheric CO2 measurements? Starting with this article in Gizmodo:
El Niño Has Pushed Our Planet Past a Major Climate Milestone and then to this commentary in Nature Climate Change El Niño and a record CO2 rise there seems to be some connection.
I'm pretty sure that El Niño does not directly produce CO2! Can someone help me understand the discussion of the relationship from a physics perspective? Did El Niño affect the measured values of atmospheric CO2? Did it result in CO2 redistribution, or aid CO2 production in some way? My understanding is that El Niño is an unusual change in temperature distribution and wind direction.
I'm not looking for individual opinions or theories, I'd like an explanation of the concepts presented in those two links, from a physics perspective. Thanks!
Images from NOAA via the Gizmodo article: As the author of the Gizmondo article you cited explains,
[...] scientists believe that emissions spiked due to a combination of warming and drying in the tropics, which can accelerate soil carbon decomposition, and large, drought-fueled fires.
Here you can find an equivalent explanation:
The atmospheric carbon dioxide concentration is rising year-on-year due to human emissions, but this year it is getting an extra boost due to the recent El Niño event - changes in the sea-surface temperature of the tropical Pacific Ocean. This warms and dries tropical ecosystems, reducing their uptake of carbon, and exacerbating forest fires. Since human emissions are now 25 per cent greater than in the last big El Niño in 1997/98, this all adds up to a record CO2 rise this year.
Here they give the same explanation and also explain how the influence of El Niño on the increase in CO$_2$ concentration was predicted using numerical models:
The following is multiple choice question (with options) to answer.
Which likely increased atmospheric CO2 recently? | [
"sustainable fisheries",
"electric cars",
"motorcycles",
"ant populations"
] | C | carbon dioxide concentrations in the air have increased over the last decade dramatically |
OpenBookQA | OpenBookQA-4597 | botany
Title: Do plants absorb toxins from the soil? Consider a plant like Aloe Vera that grows up in a toxic environment where the concentration of pesticides, and materials like lead, mercury, cadmium, arsenic etc is very high(e.g. Marshland dumping yard ). Would that mean that the extract from these plants would contain all these toxic elements. Not "all of them". But yes, plants suck up water from the soil, with everything dissolved in this water - nutrients, heavy metals, poisons. And also they breathe air, and absorb stuff via this route.
There probably are some toxins which will not enter the plant, because their molecules are too large and/or fragile. For example, should a plant root come in contact with snake venom, I cannot imagine that any venom will end up stored in the plant leaves.
Plants also have their own metabolism, so they will change/deactivate some toxins. I've seen claims that some plants "purify" formaldehyde, although I don't trust the sources enough to be sure of that.
But the smaller the poison molecule, and the less similar to stuff which is usually digested in nature, the more likely that it will enter the plant and stick around instead of being broken down. The heavy metals you mentioned are prime candidates. If they are present in the groundwater - or also lead from air pollution, before we banned leaded gasoline - they end up in plants, including food plants. And mushrooms are even more at risk.
Growing food near waste dumps is a known problem in farming, and sometimes makes the news, for example here:
http://bigstory.ap.org/article/mafia-toxic-waste-dumping-poisons-italy-farmlands
The following is multiple choice question (with options) to answer.
What absorbs nutrients from soil into themselves through their roots? | [
"flour",
"power plants",
"animals",
"flora"
] | D | plants absorb nutrients from soil into themselves through their roots |
OpenBookQA | OpenBookQA-4598 | electromagnetism, electricity, insulators
Title: How can a glass rod become charged if it is an insulator? I was reading some of the other questions, and I found this one about a glass rod and how it gains a net charge when rubbed with a silk scarf. I learned from working in a shop one summer that most solids are insulators, because their electrons are tightly bound, so it is hard to knock them off. Why would such a simple motion (like a moving scarf) knock electrons from an insulator (I looked it up and glass is an insulator)? Conductivity is not just about how tightly bound electrons are, but equally about how easy it is for them to travel.
Example: a bunch of islands in a shark-infested sea. You cannot swim from one island to the next although it is close. At low tide you can walk across no problem. The first example is an insulator, the second is a conductor.
Rubbing (google triboelectricity) causes unlike atoms to stick and unstick frequently. Atoms "fight" over electrons, and the stronger one gets to take the electron home. It is like air lifting them from the island - shark infested waters or not.
There are lists of materials (the triboelectric series) that tell you which material will give up its electrons when in contact with another material. Glass is high on the list - it loses electrons easily. The can't move sideway, but they can be picked off the surface.
The following is multiple choice question (with options) to answer.
An example of an electric insulator could be | [
"magic",
"orange juice",
"tupperware",
"milk"
] | C | brick is an electrical insulator |
OpenBookQA | OpenBookQA-4599 | zoology, digestive-system, pets
Title: Is it safe to feed an adult fire salamander with slime maggots? As a reminder, maggots feed of a flesh, while fire salamander consumes his prey alive, without killing it.
Can it happen that the maggot will start eating the salamander from the inside? Although I am afraid I don't know much about fire salamanders specifically, it is certainly possible for ingested fly larvae (or larvae hatching from ingested eggs) to survive ingestion and subsequently cause intestinal damage. Parasitic infestation by fly larvae that grow inside the host while feeding on its tissue is called myiasis. Enteric myiasis (also called gastric, rectal, or intestinal myiasis to indicate the affected part of the digestive system) occurs occasionally in humans following the ingestion of cheese infested with cheese fly maggots. Casu marzu, a traditionally produced Sardinian cheese, is supposed to have live cheese fly maggots in it, and cases of bloody diarrhoea following its consumption are known. If they're dead the cheese is considered unsafe to eat (although personally I'd correct that to 'more unsafe').
The following is multiple choice question (with options) to answer.
Which Disney character was a herbivore? | [
"Pluto",
"Cheshire Cat",
"Bambi",
"Simba"
] | C | herbivores only eat plants |
OpenBookQA | OpenBookQA-4600 | zoology
Capybara, rabbits, hamsters and other related species do not have a complex ruminant digestive system. Instead they extract more nutrition from grass by giving their food a second pass through the gut. Soft fecal pellets of partially digested food are excreted and generally consumed immediately. Consuming these cecotropes is important for adequate nutritional intake of Vitamin B12. They also produce normal droppings, which are not eaten.
Young elephants, pandas, koalas, and hippos eat the feces of their mother to obtain the bacteria required to properly digest vegetation found on the savanna and in the jungle. When they are born, their intestines do not contain these bacteria (they are completely sterile). Without them, they would be unable to obtain any nutritional value from plants.
Eating garbage and human feces is thought to be one function of dogs during their early domestication, some 12,000 to 15,000 years ago. They served as our first waste management workers, helping to keep the areas around human settlements clean. A study of village dogs in Zimbabwe revealed that feces made up about 25% of the dogs’ overall diet, with human feces making up a large part of that percentage.
Coprophagia
Daily rhythms of food intake and feces reingestion in the degu, an herbivorous Chilean rodent: optimizing digestion through coprophagy
Coprophagia as seen in Thoroughbred Foals
The following is multiple choice question (with options) to answer.
An herbivore will | [
"eat a little meat daily",
"never eat any plants",
"eat meat now and then",
"only eat things that grow out of the ground"
] | D | herbivores only eat plants |
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