Split (2)

train · 226k rows

question stringlengths 3 301	answer stringlengths 9 26.1k	context list
how does cat litter work	It's also conditioning. We teach them that this is where they go and since they naturally want to bury their droppings it works for everyone	[ "A litter box, sometimes called a sandbox, litter tray, cat pan, litter pan, or catbox, is an indoor feces and urine collection box for cats, as well as rabbits, ferrets, miniature pigs, small dogs (such as Beagles and Chihuahuas), and other pets that instinctively or through training will make use of such a reposi...
How is my hairdryer "ionic"?	I'll take a stab: I think what happens is as the air is drawn into the hair dryer, there are a set of metal plates (not sure what kind) that are charged with an electric field. As air rushes past, it is possible for some molecules of O2 or N2 (the principle components of air) as well as CO2 (a minor component) to pic...	[ "Many feature \"ionic\" operation, to reduce the build-up of static electricity in the hair, though the efficacy of ionic technology is of some debate. Manufacturers claim this makes the hair \"smoother\". Some stylists consider the introduction of ionic technology to be one of the most important advances in the be...
I have to choose a novel to read for my World Civilizations class (content from beginning of time through 1500CE) written by a historian. Any great suggestions?	Check out the [many recommendations at this past discussion] (_URL_0_). You're bound to find something to fit your interests. Once you make a choice, you could post it here and see what kinds of opinions it gathers.	[ "Several attempts have been made to create a list of world literature. Among these are the great books project including the book series \"Great Books of the Western World\", now containing 60 volumes. In 1998 Modern Library, an American publishing company, polled its editorial board to find the best 100 novels of ...
Are there any examples of venomous or toxic birds?	There's the [little shrikethrush](_URL_0_), the [blue-capped ifrit](_URL_3_), and the [hooded pitohui](_URL_1_). All three are native to New Guinea and sequester in their skin and feathers [batrachotoxin alkaloids](_URL_2_) obtained from their diet of Choresine beetles. Handling them causes numbness and tingling. Eat...	[ "Toxic birds are birds that use toxins to defend themselves from predators. No species of bird is known to actively inject or even produce venom, but some birds are known to be poisonous to touch or eat. These birds usually sequester poisons from animals and plants that they feed on, commonly from poisonous insects...
how does the new internet bill that reddit hates so much work? will i actually be able to call and request any person's web history? how will companies take advantage of this?	No, definitely not. Basically, companies can collect data on you either to sell or for their own use. Other companies can buy this data. It helps them get insight in trends for their users. While good for the business, that means your personal life is being used for monetary gain. That's what happens with grocery store...	[ "The bill faces opposition from some federal agencies, who state that they rely on subpoenas to conduct investigations. In Senate committee testimony given in September 2015, Federal Trade Commission officials expressed concern that \"recent proposals could impede its ability to obtain certain information\" from In...
why child support is based on income rather than what a child would need monthly.	Child support is partially based on income. It is also partially based on the number of children and their age, the cost of basic living expenses and school in that general area, and whether or not any special needs are present. Which sometimes leads to a very high ratio, but that is also something that can happen when...	[ "According to Jewish law, the father's income is not relevant to child support. Usually it is a multiplication of the minimum allowance of 1,400 NIS per child, multiplied by the number of children, plus a contribution to the mother's housing expenses (\"Mador\"), i.e. if the custodian mother is renting an apartment...
What was the atmosphere like when dinosaurs existed? Could humans have breathed the air?	There are no direct measures of atmospheric oxygen from that period. There are a few ideas out there about potential ways to determine atmospheric O2 concentration that far back in time. They are: Stomatal density of fossil leaves; stable carbon isotope ratios of soil carbonates (pedogenic carbonate); stable carbon iso...	[ "BULLET::::- Wieland suggested that the dinosaurs were driven extinct when the amount of carbon dioxide in Earth's atmosphere decreased until it was too low to instigate them to breathe and they suffocated.\n", "The palaeontologist Peter Ward has argued that the evolution of the air sac system, which first appear...
what is the difference between a voxel and a pixel?	A pixel is part of a 2-D image - like all the dots that make up your screen. A voxel is a 3-D element, like the cubes that make up Minecraft.	[ "A voxel represents a value on a regular grid in three-dimensional space. As with pixels in a bitmap, voxels themselves do not typically have their position (their coordinates) explicitly encoded along with their values. Instead, rendering systems infer the position of a voxel based upon its position relative to ot...
why does the skin dry up when you shave?	Your skin has a layer of oil on top of it. And hair follicles will produce an oily layer too, called sebum. When you shave, you're taking away all of that so your skin feels dry	[ "Bringing a shave brush across one's skin produces a mild exfoliation. Because a shave brush is most often used with a shave soap, this effect often replaces the pre-shave routine of washing and applying lotion to the face.\n", "Before wet shaving, the area to be shaved is usually doused in warm to hot water by s...
What did people really think of Elizabeth I?	If you're looking at film representations of Elizabeth ( which are, in their own way, a researched and visually represented vision of a historical figure and as subject to accuracy and inaccuracy as written versions ) then have a look at the [2005 Elizabeth I](_URL_0_) with Helen Mirren playing her golden years. This...	[ "Elizabeth's influence on the Queen, together with her colourful past, made her many enemies. Like her third husband she seems to have been proud, although Lord Dartmouth called her \"the best bred as well as the best born person in England\". She showed great skill in dealing with the Queen, her secret, it was sai...
why "from concentrate" juice tastes so different from "not from concentrate"	they remove the water by heating it up. heating foods and drinks alters them chemically.	[ "Juice is a drink made from the extraction or pressing of the natural liquid contained in fruit and vegetables. It can also refer to liquids that are flavored with concentrate or other biological food sources, such as meat or seafood, such as clam juice. Juice is commonly consumed as a beverage or used as an ingred...
why does great singing evoke such a strong emotional response in humans?	Not easy to answer, partially because it's hard to get funding to study something like this. Generally speaking though, music is math. The pitch of different notes in a melodies are just the number of sound waves every second (hertz). Every time the frequency doubles (or is cut in half) you get a note that sounds lik...	[ "Emotions are known to create physiological, or bodily, changes in a person, which can be tested experimentally. Some evidence shows one of these changes is within the nervous system. Arousing music is related to increased heart rate and muscle tension; calming music is connected to decreased heart rate and muscle ...
Good place to find emission spectra for compounds and elements?	Have you tried the [NIST Data Gateway](_URL_0_)?	[ "The emission spectrum can be used to determine the composition of a material, since it is different for each element of the periodic table. One example is astronomical spectroscopy: identifying the composition of stars by analysing the received light.\n", "The emission spectrum of a chemical element or chemical ...
What is the likelihood that Spain and France could have merged into one nation in the 16th century?	A reply to /u/TheUnbiasedRedditor Great question, although the answer is complicated. Poner una pica a flandes as they say in Spain. ;-) In that era, dynastic claim trumps nearly all. After all, that was how the Trastamara line lost the crowns of Spain to the Habsburgs. So in order for one nation to be absorbed by ...	[ "For much of the 18th century, France and Spain were allies but after the execution of Louis XVI in 1793, Spain joined the War of the First Coalition against the French First Republic but was defeated in the War of the Pyrenees. In August 1795, Spain and France agreed to the Peace of Basel, with Spain ceding their ...
why do certain substances (drugs, pharmaceutical drugs) need to be carefully injected in your blood in order to be effective, while others (tranquilliser darts, poison from a bite) can work regardless of where they puncture you?	It is mostly question of dose and pharmacokinetics (the speed the substance acts). When you carefully inject something into bloodstream (some bigger vein), pretty much all of it spreads around the body fast. That way you can exactly control the dose and make the most out of what you have. If you injected it elsewhere, ...	[ "Of all the ways to ingest drugs, injection carries the most risks by far as it bypasses the body's natural filtering mechanisms against viruses, bacteria, and foreign objects. There will always be much less risk of overdose, disease, infections, and health problems with alternatives to injecting, such as smoking, ...
why countries around the world teach students multiple languages at a young age, and most american students don't have the option to learn a language in school until much later?	English is the language of business in Europe and Pacific Rim. American kids learn English as their primary language. European and Asian kids don't, so they learn it as a secondary language at a young age.	[ "Many small independent nations' schoolchildren are today compelled to learn multiple languages because of international interactions. For example, in Finland, all children are required to learn at least two foreign languages: the other national language (Swedish or Finnish) and one alien language (usually English)...
When and why did we start drinking wine out of stemmed bulbous glasses, but not other drinks?	Hello. History teacher here, and I've taken a History of Alcohol class so I hope I can help a little. Sources...? I'll try to find some. But the gist of it is that the narrow stemmed wine glass owes its shape, status, and purpose to the ancient Romans. (Either late Republic or early Empire according to Pompeii/Herculan...	[ "The glass bottle was an important development in the history of wine, because, when combined with a high-quality stopper such as a cork, it allowed long-term aging of wine. Glass has all the qualities required for long-term storage. It eventually gave rise to \"château bottling\", the practice where an estate's wi...
what is the point of scientists creating new elements if they are all extremely unstable and can only exist as a few atoms for a few fractions of a second?	Solving a really hard problem usually requires one to solve many less hard problems, some of them for the first time. In solving those problems and documenting them you make it easier for future work which may come across those same problems. That's one of the cornerstones of science. In addition there's a hypothetic...	[ "The quest for new elements is usually described using atomic numbers. As of 2010, all elements with atomic numbers 1 to 118 have been observed. Synthesis of new elements is accomplished by bombarding target atoms of heavy elements with ions, such that the sum of the atomic numbers of the target and ion elements eq...
If CO2's sublimation point is -78.5C, and the coldest temperature recorded in the Antarctic was -89C, would there have been cardice on the ground as well as regular snow/ice? Were there any observations made about this?	Arguably the lowest recorded temperature is actually [92ºC](_URL_1_) observed via infrared satellite imagery. Theoretically, a [large amount of dry ice](_URL_2_) should be observable to the Landsat satellites, but Earth's atmosphere doesn't have enough CO2 for significant accumulation. [The last askscience](_URL_0_) ...	[ "Arrhenius estimated based on the CO levels at his time, that reducing levels by 0.62 – 0.55 would decrease temperatures by 4–5 °C (Celsius) and an increase of 2.5 to 3 times of CO would cause a temperature rise of 8–9 °C in the Arctic. In his book \"Worlds in the Making\" he described the \"hot-house\" theory of t...
if we have a treasury of the united states, then why did we need a bank of the united state or federal reserve today?	Treasury of the U.S. and Federal Reserve serve radically different purposes. TREASURY OF THE U.S. - Works for the U.S. Gov't as we know it (White House and Congress). - Carries out all the financial work that must be done to fund the bureaucracy that runs the country, including printing money. - Executes fis...	[ "The United States Government, on the other hand, still had limited taxation capabilities, and so had an interest in the seigniorage potential of a national bank. In 1846, the Polk Administration created a United States Treasury system that moved public funds from private banks to Treasury branches in order to fund...
the slash and axl rose fued?	Axl Rose is bipolar, which means he gets really mad/happy/sad for no reason. One time, when he was really mad, he said he would quit unless he got rights to the name (Guns N' Roses) incase they break up. A few months later, he made a whole new band with the same name, and all different people. He kicked Slash and all t...	[ "Slash is the debut solo album by Guns N' Roses guitarist and songwriter Slash. The album was produced by Eric Valentine and features multiple musicians, including four of the five members of the \"Appetite for Destruction\"-era Guns N' Roses lineup: Slash himself, Izzy Stradlin, Duff McKagan and Steven Adler.\n", ...
how do mortgage works?	A mortgage is just a special term for "home loan." Basically, since houses are too expensive to just buy, you need to get a big, huge bank loan to be able to pay for one. But banks don't just give away those kinds of loans - they need some kind of collateral, something they get to keep if you don't pay them back. An...	[ "In consumer lending, mortgage origination, a specialized subset of loan origination, is the process by which a lender works with a borrower to complete a mortgage transaction, resulting in a mortgage loan. A mortgage is a loan in which property or real estate is used as collateral. During this process, borrowers m...
when it comes to bullet calibers what do the numbers indicate? e.g 7.62x39mm, 5.56x45mm, 9x19.	Example: 5.56x45mm 5.56 means the diameter of the bullet 45 means the length of the casing	[ "The 7.62 mm designation refers to the internal diameter of the barrel at the lands (the raised helical ridges in rifled gun barrels). The actual bullet caliber is often , although Soviet weapons commonly use a bullet, as do older British (.303 British) and Japanese cartridges.\n", "The \"L56\" in the designation...
The English victory over the Spanish Armada in 1588 is mythologized as a huge upset against a global superpower; was it, in fact, a shocking outcome? How strong was the English navy at this point?	I've written about the Armada here a bit before -- I will link to that older answer. Although it's a bit before my time period, I feel confident that I can answer follow-ups if you have them. Here's the older answer: _URL_0_ The tl;dr is that essentially, the Spanish plan was not strategically sound -- the Armada was ...	[ "In 1588, Spanish King Philip II sent his Armada to subdue the English fleet of Elizabeth, but Admiral Sir Charles Howard defeated the Armada, marking the rise to prominence of the English Royal Navy. However it was unable to follow up with a decisive blow against the Spanish navy, which remained the most important...
Taxonomically, what is the distinction between a colonial organism like a siphonophore and a multicellular organism like a human?	Biologists love their nomenclature. Nomenclature separates machines from life, cats from dogs, humans from other apes, etc. It separates the various species taxonomically. When comparing two species, there are only the differences you observe. And the best way to start understanding the big picture of biology is to...	[ "In biology, a colony is composed of two or more conspecific individuals living in close association with, or connected to, one another. This association is usually for mutual benefit such as stronger defense or the ability to attack bigger prey. It is a cluster of identical cells (clones) on the surface of (or wit...
what exactly is happening when we suddenly don't need to use the bathroom anymore?	That never happens to me with poop, but rather urine quite frequently when I'm active. Maybe it sweats out? Pissing your pants by sweating? ha	[ "Functional incontinence is a form of urinary incontinence in which a person is usually aware of the need to urinate, but for one or more physical or mental reasons they are unable to get to a bathroom. The loss of urine can vary, from small leakages to full emptying of the bladder.\n", "Inability to access a bat...
why is it legal for someone to have sex with a 16 year old in most countries and most states, but if they film or take photos of the encounter, they have created child pornography?	For the US it has to do with the difference between Federal and State level law making authority. Because child pornography, as well as standard pornography laws are Federal laws they are set to the Federal age of consent which is 18. The reason that they are federal laws is that they deal with materials that cross s...	[ "of one’s age or consent to sexting, it is unlawful to produce, possess, or distribute explicit sexual images of anyone under 18.\" The University of New Hampshire’s Crimes Against Children Research Center estimates that 7 percent of people arrested on suspicion of child pornography production in 2009 were teenager...
if a virus works by injecting its dna into healthy cells, why dont we re-program the virus to inject our own healthy young dna into our cells to prevent us from aging?	They are working on things like that. Aging is more complicated than that. But it does include the fact that the Chromosomes in cells show aging. Cancer is a result of uncorrected genetic damage. Generally a virus is much smaller than our own DNA. So it is like wanting to use a back pack for a shipping container. Th...	[ "Depending on the virus, a variety of genetic changes can occur in the host cell. In the case of a lytic cycle virus, the cell will only survive long enough to the replication machinery to be used to create additional viral units. In other cases, the viral DNA will persist within the host cell and replicate as the ...
how can airlines oversell flights and then expect passengers to give up their seats?	When this happens the airline will offer perks to any passengers willing to give up their seats and will steadily increase the perks until someone cracks. The money they save by overbooking and ensuring the plane is full more than makes up for the money they lose by paying people to give up their seats.	[ "Airlines may ask for volunteers to give away their seats or refuse boarding to certain passengers in exchange for a compensation that may include an additional free ticket and/or an upgrade in a later flight. They can do this and still make more money than if they booked only to the plane's capacity and had it tak...
What is happening when we get that "scratchy tickle" sensation in the back of our throats when we get sick?	there can still be mucous running down the back of your throat even if your nasal cavities are dry. Also it could be from [natural killer cells](_URL_0_). One of the first responses of the body is for these cells to induce cell death in cells that are infected, which you can feel in the throat. Someone more sciency th...	[ "Symptoms usually began to appear six to 11 days after initial infection, beginning with a fever and cough. Most cases reported a progression to a persistent cough, leading to expectoration and sometimes hemoptysis. Worms in the bronchial region can trigger a chronic, nonproductive cough and asthma-like symptoms du...
why does a wine glass make a sound when a finger is spun on the top?	Any object has a harmonic frequency at which it vibrates best. For a thin wine glass, this might be a relatively high note which you can hear well. For a tire, it's likely too low for you to hear. When yo run your finger around the edge you stimulate vibrations, but you finger is slippery enough to not require a spe...	[ "Because its sounding portion is made of glass, the glass harmonica is a type of crystallophone. The phenomenon of rubbing a wet finger around the rim of a wine goblet to produce tones is documented back to Renaissance times; Galileo considered the phenomenon (in his \"Two New Sciences\"), as did Athanasius Kircher...
Do electric cars batteries lose the ability to be charged over time?	Yes. Generally speaking any use of a battery reduces it's capacity, even when charged and discharged "optimally". Most electric cars use some kind of lithium ion batteries. The Tesla Model S, in fact, just uses standard 18650 lithium ion batteries that you can buy anywhere. Car batteries are generally oversized and und...	[ "As with all lithium-ion batteries, electric vehicle batteries may degrade over long periods of time, especially if they are frequently overcharged, however, this may take at least several years before being noticeable.\n", "A fully depleted battery will not draw more power if the cables are reversed, but reverse...
Modern music shows examples of music that is directly associated with drug use, such as Psychedelic or Stoner Rock. Are there any examples of songs, composers, or genres in pre-modern times that had this same association?	The French composer of the Romantic Era, Hector Berlioz, composed his Symphonie Fantastique in 1830. [Both the 1845 and 1855 versions of his programme](_URL_0_) for the symphony state they describe a young musician, spurned by the one he loves, who has poisoned himself with opium. The 1845 programme suggests it's the...	[ "References to drugs can be found most abundantly in multiple types of music during the 1960s and 1970s. The new subgenre of pop and rock known as psychedelic music started becoming completely mainstream during the former decade. After 1966, with the release of The Beatles' album \"Revolver\", regular audiences emb...
why hasn’t antigravity been discovered and used yet?	Gravity appears to be one of the "fundamental" forces of the universe, meaning that you can't explain gravity in terms of anything else and you can never turn it off. For our universe to exist, it appears gravity has to exist the way it does.	[ "Physical principle surveys by Cleaver and Weyl stated the antigravity research was not based on any recognized theoretical breakthroughs. Cleaver's skepticism suggested an alternative rationale for establishing that research was based on a science fiction novel. Weyl charged publishers with poor journalism; attack...
how come doors inside the house slam shut when one to outisde is open, but i don’t feel the slightest breeze of wind myself?	It's because of pressure. The higher pressure on one side of that door causes it to shut, it doesn't necessarily need wind to cause it to shut.	[ "Windows and doors that are not fully closed can cause the alarm contacts to be misaligned which can result in a false alarm. In addition, if a door or window is left slightly ajar, wind may be able to blow them open which will also cause a false alarm. To prevent this from happening, door and windows should always...
When did commercial refrigeration become widespread and how did restaurants store perishable food like meat before refrigeration became widespread?	I'm not sure when it became widespread, but I can speak to pre-industrial refrigeration. Prior to any sort of electrical refrigeration, ice would be cut from frozen ponds and lakes during the winter, and put into pits or warehouses, typically lined with straw for insulation to prevent melting as much as possible. [Her...	[ "In the late 19th Century and into the very early 20th Century, except for staple foods (sugar, rice, and beans) that needed no refrigeration, the available foods were affected heavily by the seasons and what could be grown locally. Refrigeration has removed these limitations. Refrigeration played a large part in t...
how did people manipulate photographs before computers?	Literally cut and paste. With hands and scalpels.	[ "The use of photographs in artwork began in the early 80s with stressed and damaged photos from the Communist Revolution era. Then, during the mid to late 90s, artists used images to represent the Sino-Japanese War. After this, experimental artists began using family photos to create \"private histories.\" This led...
what was delivering a baby like for early man?	You know animals have babies in the wild, right? I would say it was pretty much like that. They didn't think anything was wrong with them, they done whatever they wanted with the extra stuff (discarded it, ate it, whatever). Granted, many more babies and women would have died as they weren't equipped to deal with com...	[ "A baby hatch or baby box is a place where people (typically mothers) can bring babies, usually newborn, and abandon them anonymously in a safe place to be found and cared for. This kind of arrangement was common in the Middle Ages and in the 18th and 19th centuries, when the device was known as a foundling wheel. ...
What effect of one big workout compared to several small workouts? (throughout the course of a day)	Hey guys! Let's keep this on topic and scientific. No bro science please, only documented studies from journals, textbooks, etc. Thank you!	[ "The physiological effects of training have received much further study since Cooper's original work. It is now generally considered that effects of exercise on general metabolic rate (post-exercise) are comparatively small and the greatest effect occurs for only a few hours. Though endurance training does increase...
Can we make small, lab-sized, analyzable nuclear explosions?	Depends on the size of the lab? But for a "classical" nuclear explosion to occour you need a "critical mass". This the minimum mass of nuclear material that can go critical (explode). Assuming you're not using any special technology to encourage criticality other than high explosives like in a classical nuclear bomb;...	[ "As a comparison, the blast yield of the GBU-43 Massive Ordnance Air Blast bomb is 0.011 kt, and that of the Oklahoma City bombing, using a truck-based fertilizer bomb, was 0.002 kt. Most artificial non-nuclear explosions are considerably smaller than even what are considered to be very small nuclear weapons.\n", ...
why do old movies and videos have this sorta staticky sound in the background and modern ones don’t?	A lot of reasons: Old movies had the soundtrack imprinted on the film, it was analogue and intrinsically noisy - like cassettes, the same was true of video. Also copying the film to make a new print or change the format would introduce more noise. To deal with that Cinemas had quite sophisticated analogue noise reduct...	[ "Rather than synchronize every sound on screen with a shown action, \"The Virginian\" treated sound as at times being independent of the action; this allowed for greater symbolism. The film also heavily used natural sounds, such as cattle. This was facilitated by the outdoor shooting locations.\n", "The film feat...
in court why can you represent yourself but if you want someone else to represent you they need to accredited?	Because if you are incompetent, your choice to represent yourself only harms yourself. It is the same reason you can work on your own house, but contractors need to have certification.	[ "In \"Faretta v. California\", the Supreme Court of the United States held that criminal defendants have a constitutional right to refuse counsel and represent themselves in state criminal proceedings. That said, the right to represent oneself is not absolute. It is the Court's right and duty to determine if a part...
When a protostar begins fusion and becomes a star is there a sudden release of energy?	A sun is not a light bulb. There is not one instant in time when it dramatically "begins fusion." Stars form from the gravitational collapse of large clouds of gas. The core of such a region becomes a star. As time goes on, more and more material falls into this region. At some point, the pressure and temperature at th...	[ "When a protostar is formed from the collapse of a giant molecular cloud of gas and dust in the local interstellar medium, the initial composition is homogeneous throughout, consisting of about 70% hydrogen, 28% helium and trace amounts of other elements, by mass. The initial mass of the star depends on the local c...
Why do different materials sound different?	Imagine the sound that a square sheet of steel makes when you tap it with a fork. _Ping_. When you tap it with the fork you create a little deformation right at the spot the fork hit. Steel has some decent elasticity, some springiness and stiffness to it, so if you were to zoom in with a microscope, you'd see something...	[ "BULLET::::4. Overlap and insertions of widely different materials, e.g. a bird call in a melodic line. Different materials sound irrespective of one another leading to novel sound effects, and, more subjectively, multiple layers and perhaps the feeling of spaciousness.\n", "Glass is relatively hard and heavy in ...
why are graphing calculators so expensive when you can download them for free?	One of the major issues with TI emulators is that, if you let students use an app on their smartphone during a test, then you're also running the risk of giving them internet access, and other capabilities of the phone you might not want in a testing environment.	[ "Since graphing calculators are usually readily user-programmable, such calculators are also widely used for gaming purposes, with a sizable body of user-created game software on most popular platforms. The ability to create games and other utilities within most graphing calculators has spurred the creation of nume...
why do football fans give tim tebow so much attention?	He wasnt a great NFL player. Coming out he was one of the most hyped College Players in YEARS. 2 National Championships and a Heisman to his name during his time at Florida. Basically Johnny Manziel if Johnny had actually won more games in college. That and his strong social example made him easy to cover.	[ "The show has been criticized for what is perceived by many as its excessive coverage of the career of Tim Tebow. During his tenure with the Jets, in which he did not start in a game, and threw just eight passes the entire season. Tebow was nonetheless often a leading topic.\n", "The performances of quarterback T...
why can't people donate insulin like they donate blood?	Your insulin is released from your pancreas as you need it to deal with the sugar in your blood. We can’t remove your pancreas to get at the bits that make the insulin because that would not only be inefficient but would also make you a diabetic. And you may carry diseases in your body parts that could infect someone e...	[ "Insulin therapy creates risk because of the inability to continuously know a person's blood glucose level and adjust insulin infusion appropriately. New advances in technology have overcome much of this problem. Small, portable insulin infusion pumps are available from several manufacturers. They allow a continuou...
why disposable razors go dull in a week or two, but electric razors take years.	Many electric razors cut more like scissors where the hair has to go past a stationary guard which has a rotating blade on the other side. Feel a good pair of scissors and you will notice that you will probably not get cut touching the cutting edge, but a razor is much sharper than scissors. The cutting edge of the raz...	[ "Finally, a well-kept razor can last for decades, and can become a family heirloom that can be passed from parent to child. For all of these reasons, devotees of the straight razor make for an active market.\n", "After their introduction in 1680, straight razors became the principal method of manual shaving for m...
How does human hair dull stainless steel razor blades? Is it possible to make a blade that will last a lifetime of use?	> > Because you know...for science Its a great question - hair feels soft - even tough male beard hair seems extremely soft compared to steel ...but we are looking at things with human eyes and human sense of touch. Lets start by looking at a used razor blade _URL_2_ you can see the edge looks dull. Now lets look...	[ "A straight razor blade (cut-throat razor) starts, at the Thiers Issard factory, as a shape called the blank supplied by the steel manufacturer. Thiers Issard traditionally has used Sheffield silver steel, long considered a superior quality carbon steel. The first step is to clean the blank using a heavy forge proc...
if cockroaches are able to survive nuclear radiation,what the hell do they put in anti-cockroach sprays like raid?	TL;DR: Roaches cells don't divide very often which protects from radiation poisoning, but they have no real defense against the neurotoxins in raid. It basically boils down to the mode of action for why causing death. Radiation and YOU To understand why radiation is considered bad for people, and not (seem...	[ "It is popularly suggested that cockroaches will \"inherit the earth\" if humanity destroys itself in a nuclear war. Cockroaches do indeed have a much higher radiation resistance than vertebrates, with the lethal dose perhaps six to 15 times that for humans. However, they are not exceptionally radiation-resistant c...
Is there a physical way to prove that the shapes of electron clouds?	You can't really prove it, but you can get pictures that kind of resemble it by using scanning tunnelling electron microscopy. IBM has pictures of the molecular orbitals of a salt molecule: _URL_0_ Figure 1 on the right (click on its text to make it pop up bigger) compares two tunnelling microscope pictures of a salt...	[ "Edelsbrunner's most heavily cited research contribution is his work with Ernst Mücke on \"alpha shapes\", a technique for defining a sequence of multiscale approximations to the shape of a three-dimensional point cloud. In this technique, one varies a parameter alpha ranging from 0 to the diameter of the point clo...
what makes a modern internal combustion engine built today different from the ones fifteen, or even ten years ago?	Electronics and the degree of monitoring and control are really what sets engines apart. Fuel injection that is tailored at all times to the needs of the engine allow cars to be much more powerful, much more efficient, and at the same time produce far less pollution. The general ideas of the combustion engine are not n...	[ "The first commercially successful internal combustion engine was created by Étienne Lenoir around 1859 and the first modern internal combustion engine was created in 1876 by Nikolaus Otto (see \"Otto engine\").\n", "As of 2017, the majority of the cars in the United States are gasoline powered. In the early 1900...
the burj khalifa cost 1.5 billion $ to construct. what stops the richest people in the world to simply "outperform" that by building the bew tallest building?	Nothing, but building the tallest building in the world doesn't necessarily mean it will be a good investment on you money. That's a lot of money to spend on bragging rights.	[ "The Burj Khalifa is the world's tallest building, with a total height of 829.8 metres (2,722 ft) and a roof height (excluding antenna) of 828 m (2,717 ft). Construction began in 2004 and the building was opened in 2010. The total cost of construction is estimated to be US$1.5 billion.\n", "Burj Khalifa is the ce...
Why did the Roman Empire have so much trouble establishing a long-lasting dynasty, while other empires before and after Rome did not?	It has to do with the way the Romans interpreted families and inheritance. u/mp96 gave [a comprensive answer to a similar question here](_URL_0_). It might interest you that our concept of inheritance and absolutism is a construct that had not yet emerged in the Roman empire: > During the late Roman and Merovingian/...	[ "Fundamental problems with the empire still remained. The right of imperial succession had never been clearly defined, which was a factor in the continuous civil wars as competing factions in the military, Senate, and other parties put forward their favored candidate for emperor. The sheer size of the empire, which...
why is there a buffeting sound when my car passes guard rails or other evenly spaced things?	That's just the sound of your car reflecting off of the objects as they pass by. Since the objects are evenly spaced, the sound gets reflected again and again at regular intervals.	[ "A critical issue is that there are no barriers or lights at level crossings, only a warning sign at every one of the many grade crossings. Train airhorns are used to warn pedestrians and cars at every grade crossing of an incoming train. This is in order to prevent accidents, which have been registered, but due to...
why does torrents have such weird names?	It's a naming standard for the servers that the uploaders use. The full standard is: Title.Of.The.Movie.YEAR.Source.Codec-GROUP For example, BDRip is a file ripped from a blu-ray disc. x264 is the coded used to compress the video. Sujaidr is the name of the group/person responsible for the upload.	[ "The author of µTorrent wrote in 2005, \"I usually say 'you torrent' because it looks like a u\", and offered \"microtorrent\", \"mytorrent\" (as \"my\" is the Swedish pronunciation of the Greek letter µ) and later \"mutorrent\" as alternative pronunciations. In Greece, where the software is widely \n", "The name...
What effect might the measures to fight Covid-19 around the world have on more common illnesses?	It’s hard to be sure, but it looks as if social distancing, etc, may be reducing flu. In the Northern hemisphere, flu is already waning as flu season ends, but it’s expected to be just starting up in the Southern Hemisphere. A very early and preliminary look ([FluTracking Reports (Australia)](_URL_0_)) shows possible f...	[ "In past it was believed that GH treatment could increase the cancer risk; a large study recently concluded that \"With relatively short follow-up, the overall primary cancer risk in 6840 patients receiving GH as adults was not increased. Elevated SIRs (which is risk of getting cancer) were found for subgroups in t...
why do most keyboards limit what keypresses register when certain other keys are already held down?	Buttons on most keyboard are not in fact buttons in the usual sense, keyboards have three plastic layers to which two have a grid of wires on them and the third between them holds them seperate with holes where the keys are. (Think of a sandwich with swiss cheese). When you push a key on the keyboard, a rubber plunger ...	[ "A keyboard with \"two-key rollover\" can reliably detect only any two keys used simultaneously; in other words, a user can hold down any key on the keyboard and press a second key, and be sure that the keypress is correctly detected by the computer. However, if the user has two keys depressed and attempts to strik...
Do subliminal messages really work?	Almost certainly not. Subliminal messages are just messages that fall below the human threshold for perception. People often connect them with their sub-concious, which is wrong. They have no more effect on your subconscious that any regular message you come across. If it did work, it would almost certainly be in comm...	[ "Applications of subliminal stimuli often base themselves on the persuasiveness of the message. Importantly, research on action priming has shown that subliminal stimuli can trigger only actions a receiver of the message plans to perform anyway. However, consensus of subliminal messaging remains unsubstantiated by ...
can someone please explain why they always insist on specifying the counts of "infants" separate from "people" and or "citizens" after mass casualty incidents.	In some peoples' moral beliefs, an infant/child life could be considered more valuable because they have the most potential in life.	[ "As the probability of an individual surviving until age \"t\" or later is \"S\"(\"t\"), by definition, the expected number of survivors at age \"t\" out of an initial population of \"n\" newborns is \"n\" × \"S\"(\"t\"), assuming the same survival function for all individuals. Thus the expected proportion of survi...
Why does it take so long for snowmen/packed snow to melt compared to unpacked, fallen snow?	Essentially it’s density. Packed snow has more snow in a smaller area so there is less surface area for heat transfer. for example, a ball of snow is exposed to the sun less than an equivalent amount of snow laid out flat. Also the snowball can disperse the heat it’s absorbing much more because there are more particl...	[ "Light snow falls most winters, and melts quickly. Heavy snow falls once or twice a decade, such as in March 2006 (see picture in the Hiking and bicycling section). On December 7, 2009, the snow level dropped to and snow remained for three days.\n", "In most of the Arctic the significant snow melt begins in late ...
Why does ethanol evaporate out of my cleaning solutions or off the glass im cleaning but not out of my gin and tonic?	Well, it does in both cases. It's just a question of rate. Assuming ideal behaviour, [Raoult's Law](_URL_0_) says that the vapour pressure of substances in a mixed solvent system reflect their relative composition in the solvent. So the component that makes up more of the solvent will end up being more of the vapour,...	[ "A downside of using alcohol as a solvent is that ethanol has a tendency to denature some organic compounds, reducing or destroying their effectiveness. This tendency can also have undesirable effects when extracting botanical constituents, such as polysaccharides. Certain other constituents, common among them prot...
Why was the SR-71 Blackbird retired from service, but the older U-2 spy plane kept in service?	In short, the SR-71 was a very niche design for strategic reconnaissance, while the U-2 was more versatile. & #x200B; The SR-71 is famous for its unmatched performance, but that performance came at the cost of operational flexibility. It was absurdly expensive to operate - \~$85,000 an hour in the late '80s - and sl...	[ "The B-18s remaining in the continental US and in the Caribbean were then deployed in a defensive role in anticipation of attacks on the US mainland. These attacks never materialized. B-17s supplanted B-18s in first-line service in 1942. Following this, 122 B-18As were modified for anti-submarine warfare. The bomba...
Heisenberg's Uncertainly principle and the Bohr Model, don't they really prove Planck's black-body radiation law?	The Bohr model can't really 'prove' Planck's black-body law. It assumes (ad-hoc) that angular momentum is quantized, without any rationale, really. (Except the one given later by de Broglie in terms of de Broglie-wavelengths) The Bohr model doesn't obey the uncertainty principle, the Schrödinger equation does. Note th...	[ "Planck's law may be regarded as fulfilling the prediction of Gustav Kirchhoff that his law of thermal radiation was of the highest importance. In his mature presentation of his own law, Planck offered a thorough and detailed theoretical proof for Kirchhoff's law, theoretical proof of which until then had been some...
Would it ever be possible to send and receive power/electricity through the air?	> Obviously they're is wireless charging, but that requires the source and receiver to touch. It doesn't. It just requires the source and receiver to be very close to each other. You can verify this by placing some additional layer between the two (for example a phone case). Alternatively, try using a contactless cr...	[ "Power might also be transmitted by changing electromagnetic fields or by radio waves; microwave energy may be carried efficiently over short distances by a waveguide or in free space via wireless power transfer.\n", "Wireless power transfer is a process whereby electrical energy is transmitted from a power sourc...
if we had an abundance of all the elements, could we have a machine which uses the elements a like toner in a printer to make whatever we want?	No. If I gave you all the ingredients necessary to build a human body (they're all cheap and widely available), would you be able to build a machine that could construct a human body? Availability of raw material is only one part of making something. You have to be able to put the parts together properly as well. For ...	[ "Electrical elements such as inductors and capacitors used in electrical analog computers had to be carefully manufactured to reduce non-ideal effects. For example, in the construction of AC power network analyzers, one motive for using higher frequencies for the calculator (instead of the actual power frequency) w...
why do we tip bar men and women in america 1 dollar per drink? doesn't this mean they would earn well over 100 dollars per hour in a busy bar?	I am a bartender, can confirm most people don't tip 1 dollar per drink. I'll give tonight as an example. I work at a casino and the bar I was working at was rather busy. 5 people working at it. Our total sales just for our bar was around $7300. So if everyone tipped $1 per drink(we will say an average drink is $5) that...	[ "Pay is usually determined by commission on drink sales with hosts often drinking far past a healthy limit, usually while trying to hide their drunkenness. Because the base hourly wage is usually extremely low, almost any man can become a host regardless of looks or charisma (depending on the bar). However, hosts w...
Blood cell survival post donation.	No. Blood cells are produced in the bone marrow, not from other mature blood cells. Mature red blood cells also do not have nuclei and thus, no DNA. However, if person B got a bone marrow transplant from person A, A would not only continue to produce blood cells from B but also white blood cells which do have nuclei an...	[ "Research published in 2012 demonstrated that repeated blood donation is effective in reducing blood pressure, blood glucose, HbA1c, low-density lipoprotein/high-density lipoprotein ratio, and heart rate in patients with metabolic syndrome.\n", "During a platelet donation, the blood is drawn from the patient and ...
why do people seem to get more personal and open when speaking to them at night?	Perhaps it's associated with [decision fatigue](_URL_0_)? At the end of the day, people are tired, their "filter" is slipping, they're more likely to open up and let things out. I know I've had countless experiences where something I've said in conversation at night seemed perfectly rational, even important, but felt...	[ "Rudnick has observed that the best use of the night is to speak to many potential romantic or business contacts over the course of the night, and to follow up and stay in touch with them over the following months to see what develops, instead of spending the entire night talking with only one person.\n", "Across...
Why was torture believed to generate genuine confessions during witchcraft trials?	I'd recommend reading "Cunning-Folk and Familiar Spirits" by Emma Wilby. In it, she makes a convincing case that there was a survival of pre-Christian fairy faith into early modern Britain, and that in many of the witchcraft cases she examines, the people charged were practicing what they believed to be magic with the ...	[ "Only in the 17th century was it realized that truthful confessions could not be made under torture. During the Enlightenment a rational interpretation of the legend came to prevail with Girolamo Tartarotti, who in 1749 explained the witches' flight as a hallucination provoked by the Devil, or Ludovico Antonio Mura...
Why is copper our material of choice for water pipes?	Copper sits in the 11th group of the periodic table, which puts it above silver and gold, which are known for being fairly stable when exposed to water. One could use silver which is a known anti-microbial for plumbing, but this would be jolly expensive. Silver is in the solder that creates the join the same reason. ...	[ "Copper pipe and tubing was widely used for domestic water systems in the latter half of the twentieth century. Demand for copper products has fallen due to the dramatic increase in the price of copper, resulting in increased demand for alternative products including PEX and stainless steel.\n", "Because the sour...
Earth has seasons because our planet's axis of rotation is tilted at an angle of 23.5 degrees relative to our orbital plane. How common is this axial tilt on other planets and can we assume a planet needs to have seasons in order to support life?	There's a range of axial tilts [within the solar system](_URL_0_). There has been [some work](_URL_1_) suggesting that no axial tilt would result in an inhospitable planet with the tropics too hot and the poles too cold. Conversely, too tipped may result in most of the planet having 6 months of light and 6 months of da...	[ "The seasons occur because the Earth's axis of rotation is not perpendicular to its orbital plane (the plane of the ecliptic) but currently makes an angle of about 23.44° (called the obliquity of the ecliptic), and because the axis keeps its orientation with respect to an inertial frame of reference. As a consequen...
In humans who are tetrachromats, what is the wavelength of the additional color they’re seeing?	Here's [a good review article](_URL_0_) that summarizes what little is known. The effect is really subtle, because: 1. The human color vision system has the peak sensitivity of the red and green cones really close together, and then a big gap before the blue cone. If an engineer were to design a four-channel color...	[ "The normal explanation of tetrachromacy is that the organism's retina contains four types of higher-intensity light receptor (called cone cells in vertebrates as opposed to rod cells, which are lower-intensity light receptors) with different absorption spectra. This means that the organism may see wave-lengths bey...
Why are the Muslim-majority areas in the Indian subcontinent in the east and west, but not the middle?	The Mughal empire did indeed sprawl over most of what we now call India - Aurangzeb extended it almost all the way south, just north of Kerala and Tamil Nadu. However, Muslims never formed a majority in almost any of these areas, at any point in time. The Mughal Empire is an interesting in that it may have been termed ...	[ "West (despite being geographically in the east), while Islamic nations are, regardless of location, grouped in the East. However, there are a few Muslim-majority regions in Europe which do not fit this dichotomy. The culture line can be particularly difficult to place in regions of cultural diversity such as Bosni...
"Feudalism" and Administration in Late 9th Century Northern Italy?	At the time of Louis II the kingdom of Italy was divided into comitati, managed by comites. These were appointed by the Emperor and not yet hereditary. The important ones went to the loyal friends or courtiers of the Emperor. There were marchioni, too, who were just more powerful than counts and sometimes in charge of ...	[ "A number of primitive feudal entities developed in the \"Marca Hispanica\" during the 9th century. They were generally self-sufficient and agrarian, but ruled by a small military elite. The pattern seen in Catalonia is similar to that found in similar border lands or marches elsewhere in Europe.\n", "The conques...
When and why did culturally distinct pockets of Jewish population become scattered across an otherwise fanatically Christian Europe in the Middle Ages?	There are myriad reasons for how the Jews became scattered across Christian Europe. Generally speaking, however, Christian rulers often invited Jews to settle within their realms, and just as often expelled them, forcing the Jews to find other homes elsewhere on the continent, and so on. The aim of this reply is to exp...	[ "From the end of the 12th century and the beginning of the 13th century, organized Jewish communities in Eastern Europe began to form. The growth of their population stemmed mainly from large migration from Central Europe in large numbers. Even non-Ashkenazi Jews settled in Eastern Europe, but their number was rela...
why are umbrellas made out of metal rods? shouldn’t they be made out of skinny pvc pipe or something?	There are several reasons but most easily to say: Tradition - Wooden and metal umbrellas have traditionally been the materials of choice in use for the umbrella shaft and skeleton. Weight vs. Strength - Metal can be made thinner, lighter and stronger than pvc and it is more versatile than plastics are. As ubiquitous ...	[ "Generally there are three types of rods used today graphite, fiberglass, and bamboo rods. Bamboo rods are the heaviest of the three, but people still use it for its feel. Fiberglass rods are the heaviest of the new chemically-made material rods. They are mostly popular with the new and young anglers, as well as an...
Did Native American societies treat gold in the same way as Europeans (as wealth or a symbol of wealth) prior to first contact?	For people living in eastern North America prior to the arrival of Europeans, gold wasn't one of the metals they utilized. There just isn't much of it in the area, and what gold does exist is hard to extract. There are some gold artifacts made by the Calusa and their tributary communities in southern Florida, but none ...	[ "The indigenous peoples in north-west America had traded in copper nuggets prior to European expansion. Most of the tribes were aware that gold existed in the region, but the metal was not valued by them. The Russians and the Hudson's Bay Company had both explored the Yukon in the first half of the 19th century, bu...
do the lithium ion batteries in "hoverboards" pose a notably greater fire-risk than the batteries in laptops, phones, and other devices?	The batteries are not more risky, the overall circuit is more risky. Laptops, phones, and other such gadgets consume very small amounts of electricity at mostly consistent rates. This is the least stressful way for a battery to be used, and so they have pushed for very high power densities. Alas, the "hoverboard" us...	[ "A disadvantage of lithium-titanate batteries is that they have a lower inherent voltage (2.4 V), which leads to a lower specific energy (about 30–110 Wh/kg) than conventional lithium-ion battery technologies, which have an inherent voltage of 3.7 V, although some lithium-titanate batteries are reported to have an ...
What happened in the 1970s to change wages v productivity so much?	One of the more persuasive recent explanations of what happened comes from [Thomas Piketty](_URL_0_). He argues that since the 1970s the rate of return on capital (i.e., securities, real estate, plants, machinery) has outstripped the overall rate of economic growth, leading to increasing inequality in the US and other ...	[ "The first three decades of the 20th century saw economic output surge with electrification, mass production and motorized farm machinery, and because of the rapid growth in productivity there was a lot of excess production capacity and the work week was being reduced. The dramatic rise in productivity of major ind...
When did the concept of “age” as a measure of years come into existence?	Followup question: was this sort of thing influenced by climate/biome? I'd imagine the presence or absence of cleanly delineable seasons would have an impact on an ancient culture's concern with measuring years before the adoption of agriculture.	[ "Old age comprises \"the later part of life; the period of life after youth and middle age . . ., usually with reference to deterioration\". At what age old age begins cannot be universally defined because it differs according to the context. The United Nations has agreed that 65+ years may be usually denoted as ol...
why is it considered unhygienic to use wooden cutting boards (due to their porous nature) but most chefs recommend using wooden spoons regularly?	how often do you stick your cutting board in boiling water? Anyway, using wooden cutting boards is fine.	[ "This technique is useful for the simple splitting of wood for kindling, to access dry wood within a wet log, and for the production of shingles, slats, or boards. It is also useful for cutting notches, or making clean crosscuts against the grain of the wood. The technique is also especially useful when a chopping ...
what is "grim trigger" in game theory, and what would it look like in international relations?	This answer was posted in another thread after yours, but answers the same question perfectly: _URL_0_ > Grim trigger is a game theory term that means once the person on the other side of the game "defects" (meaning does the selfish thing) then you defect for every play of the game after that point, with no exceptio...	[ "\"The Trigger\" is a short story written by Gillen, published in the 2017 \"Star Wars\" anthology \"From a Certain Point of View\". Set during the 1977 \"Star Wars\" film on the day that the Empire destroys the planet Alderaan with the Death Star, the story finds Aphra captured by Imperial troops and reacting to t...
Since parts of Africa were taken over by the Roman Empire, did early African culture have any influence on the post-Roman world (like Medieval Europe for example)?	I can't speak for post-Roman, but for Roman/late-Roman, certainly! North Africa was a major center of scholarship and rhetoric--St. Augustine, the most important Christian thinker, was from North Africa. Egypt is a little bit more complicated, because it was heavily romanticized and "orientalized" during the Greek and ...	[ "By the end of the Western Roman Empire nearly all of the African province was fully romanised, according to Mommsen in his \"The Provinces of the Roman Empire\". Roman Africans enjoyed a high level of prosperity. Such prosperity (and romanisation) touched partially even the populations living outside of the Roman ...
how can birds see depth (for example, when landing) if they can only see with 1 eye?	Motion. If you move your head from one place to another, you have two images to compare, just like having two eyes. You only need stereo vision to have motionless depth perception.	[ "Most birds cannot move their eyes, although there are exceptions, such as the great cormorant. Birds with eyes on the sides of their heads have a wide visual field, useful for detecting predators, while those with eyes on the front of their heads, such as owls, have binocular vision and can estimate distances when...
Monday Methods: Eric Hobsbawm and the Invention of Tradition	The concept of invented traditions is doubly important in classical studies. The first is the invented traditions of the ancient world itself: for Athens, we might look to their very strongly held idea of autochthony (roughly, indigeneity) and the way that this was used in the unification of the Attic plain, as well as...	[ "One reviewer noted that the \"'invention of tradition' is a splendidly subversive phrase,\" but it \"hides serious ambiguities.\" Hobsbawm \"contrasts invented traditions with what he calls 'the strength and adaptability of genuine traditions.' But where does his 'adaptability', or his colleague Ranger's 'flexibil...
Did people in the past have a concept of “working out” to stay fit? I know soldiers of ancient times and such must have done some physical exercise to fight well but what about others?	[The FAQ](_URL_1_) has some questions and answers that might interest you: - [How strong/muscular were ancient warriors? Did they know enough about muscle growth to be the same build as many athletes/bodybuilders now? When did humans start becoming adept at bodybuilding?](_URL_0_) has some interesting answers, particu...	[ "Hippocrates, an ancient Greek physician, believed that athletes who walked after exercising would have a stronger and more rested body. Because of his beliefs, ancient Greek athletes ended each workout with a low-intensity cool down. Aristotle observed that athletes who have a rest day should not rest completely b...
how efficient are humans at generating electricity (through an exercise bike for example) relative to food intake?	Let's take a man who works hard and eats 4 million calories/day(about what's recommended for intense physical work), he also can sustain solid 75 watts of work for all of his 8 working hours. 1 watt is 1 joule/second, so it's 75\8\60\*60 = 2160000 joules of mechanical energy. Let's say you can convert it to electric...	[ "The efficiency of human muscle has been measured (in the context of rowing and cycling) at 18% to 26%. The efficiency is defined as the ratio of mechanical work output to the total metabolic cost, as can be calculated from oxygen consumption. This low efficiency is the result of about 40% efficiency of generating ...
How do scientists get to know how complex biological systems like the Krebs cycle work on a molecular level?	How did they do it (back then?) or how do they do it now? By using experiments and logical reasoning. You can't put a cell under a microscope and watch its metabolic functions. Instead you have to extrapolate out based on the inputs/outputs of the cell. In fact, the citric acid cycle was first postulated from experim...	[ "Two key classes of regulatory molecules, cyclins and cyclin-dependent kinases (CDKs), determine a cell's progress through the cell cycle. Leland H. Hartwell, R. Timothy Hunt, and Paul M. Nurse won the 2001 Nobel Prize in Physiology or Medicine for their discovery of these central molecules. Many of the genes encod...
During WWII, where would citizens of a French or German city live while fighting was going on in their city, and after it had been demolished?	Well. In a lot of cases they stayed where they could. If there was money or family connections they might have traveled to safer areas such as the country, much like Londoners during the Blitz. The poorer citizens, however, remained in their front line cities, hiding in basements and subways hoping for the best.	[ "During World War II every town had one, and several were present in each large city. Even after the danger of bombings had ended, they were kept to provide warning in case of any threat (e.g. high water in Venice).\n", "The Germans occupied the city during War War II from 1941 - 1944. A witness recounted of the ...
the light dependent and the light independent stages of photosynthesis.	The light stage is the part where light excites electrons in the photosystems; the energy of the excited electrons is used to generate ATP and NADPH. The light independent stage is the stage where Carbon is assimilated through the calvin cycle. This uses the energy and reducing power derived from ATP and NADPH which w...	[ "Photosynthesis occurs in two stages. In the first stage, \"light-dependent reactions\" or \"light reactions\" capture the energy of light and use it to make the energy-storage molecules ATP and NADPH. During the second stage, the \"light-independent reactions\" use these products to capture and reduce carbon dioxi...
Why does water freeze in my refrigerator in one container but not in the other? Pictures in comment.	Take the containers out, thaw and rinse them, re-fill with water and then put them back in the opposite positions. Inform us what happens.	[ "“The water freezes and the germs are in the water. The freezing does not kill the germs for they are very resistant to cold and they remain in the ice until liberated by its melting when placed in water, or milk, or in contact with food taken into the system.\n", "A reviewer for \"Physics World\" writes, \"Even ...
why while cell phones continue to get slimmer, house phones are still bulky?	Because cell phones are portable, they are small and compact by design. House phones are bound to a nearby outlet anyway, so size doesn't matter	[ "In the early days of cellular phone growth, wireless companies were concerned about showing investors a return and profits sufficient to cover the infrastructure costs. Cell phone towers situated in urban areas are typically not attractive and NIMBY neighbors made those costs higher. The carriers needed wide retai...
In terms of quality of life would it be generally better to be a 3rd century Roman slave or a 12th century English peasant?	It depends a lot - there were highly valued house slaves (such as Greek tutors, book keepers, chefs etc.) that were treated almost as family and often given free upon the death of their master in Rome. These slaves were often allowed to form families, could be allowed days off and even an allowance. There were agricu...	[ "In urban workplaces, the occupations of slaves included fullers, engravers, shoemakers, bakers, mule drivers, and prostitutes. Farm slaves (\"familia rustica\") probably lived in more healthful conditions. Roman agricultural writers expect that the workforce of a farm will be mostly slaves, managed by a \"vilicus\...
i've read a lot of comments saying that politicians use war for their own gains. let's say it's true, how?	1. They have financial interests in companies that profit from war--arms manufacturers. 2. They will profit from the outcomes of war, by expanding their power and influence over a subdued territory or area. Business interested in expanding in the area or use resources from it may engage in donating or even kick backs...	[ "Political historians, such as Samuel P. Huntington and Charles Tilly, postulate that war is the primary incentive for states to invest in fiscal capacity. In \"War Making and State Making as Organized Crime\", Tilly models the government as a self-interested, power-holding actor that wishes to extract revenue from...
where did the strange idea of astrological signs effecting someone's personality come from?	Astrology was first developed both as a curiosity and a necessity for temperate agrarian societies. Learning to track when to plant and harvest and how much longer winter would be was tremendously important, and astrologers could determine the season based on what stars were coming up over the horizon. The astrological...	[ "By a process known as self-attribution, it has been shown in numerous studies that individuals with knowledge of astrology tend to describe their personalities in terms of traits compatible with their astrological signs. The effect is heightened when the individuals were aware that the personality description was ...
Why do humans get "the shakes" from cannibalism? Do animals experience this?	The disease state you are referring to is Kuru, which is caused by prions. Prions can be viewed as a protein "poison". It is a misfolded protein that, upon contact with its non misfolded form, causes the normal protein to misfold. This ends up causing a deadly cascade of misfolding of proteins which leads to neurolog...	[ "Zoonosis affecting domestic animals is caused by contact with milk, urine, and genital organs, which concentrate the causative organisms. Some reservoirs include buffalo and other animals, but mostly cattle. In humans, the disease is acquired from unpasteurised milk and products or undercooked meat (consumers), la...
How is the Hubble Telescope still finding things after 30 years?	The Hubble Space Telescope is optimised for taking very sensitive and high resolution images of very small patches of sky. Each image is really a very small part of the sky. As an extreme example, the Hubble Ultra Deep Field is about a 1% of the angular area of the Moon, and took a total of about 11 days of exposure t...	[ "The Hubble Space Telescope is a space telescope created by NASA, and was launched into low Earth orbit in 1990. It is still in operation today. The Hubble Space Telescope's four main instruments observe in the near ultraviolet, visible, and near infrared spectra. Hubble's images are some of the most detailed image...
if heterochromia is a dominant trait why don't more people have it?	A dominant trait means that the trait will manifest if you get the dominant gene from at least one of your parents. On the contrary, if the trait is recessive then it means that you have to get the recessive gene from both your parents in order for it to manifest. However, the gene's dominance doesn't directly influen...	[ "Though multiple causes have been posited, the scientific consensus is that a lack of genetic diversity is the primary reason behind heterochromia. This is due to a mutation of the genes that determine melanin distribution at the 8-HTP pathway, which usually only become corrupted due to chromosomal homogeneity. Tho...
How does amnesia work. Is it as common as movies portray?	I assume you're talking about amnesia following a head injury? Let's ignore the frequency of amnesia for a minute, and talk first about whether or not movies accurately portray amnesia. No, they do not. Not even a little bit. Again, I'll assume you're talking about the soap opera amnesia (i.e., hit head, wake up in...	[ "Movies often restore victim's memory through a second trauma, or through a kind of cued recall when they revisit familiar places or see familiar objects. The phenomenon of the second trauma can be seen in \"Singing in the Dark\" (1956) where the victim experiences the onset of amnesia because of the trauma of the ...

Subsets and Splits

No community queries yet

The top public SQL queries from the community will appear here once available.