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What kind of systems use fluid to transmit pressure and increase force?
electromagnetic systems
plumbing systems
thermal systems
hydraulic systems
Hydraulic car lifts also use fluid to transmit pressure and increase force. The lifts are used to raise cars, which are very heavy, so mechanics can work on them from underneath. Controls in airplanes use fluids to transmit pressure and increase force so a flick of a switch can raise or lower heavy landing gear. To see...
What organ interprets what our sensory organs sense?
thyroid
nerves
lungs
brain
Sensory neurons in each sense organ receive stimuli, or messages from the environment that cause a response in the body. For example, sensory neurons in the eyes send messages to the brain about light. Sensory neurons in the skin send messages to the brain about touch. Our sense organs recognize sensations, but they do...
Gametes are products through meiosis in which organs?
kidneys
hormones
cones
gonads
At the end of meiosis, haploid cells are produced. These cells need to further develop into mature gametes capable of fertilization, a process called gametogenesis ( Figure below ). Animals produce gametes directly through meiosis in organs called gonads. Gametogenesis differs between the sexes. In the male, the produc...
Haumea, which is the third brightest kuiper belt object has an odd oval shape which is probably caused by what?
Slow rotation
unusually rapid rotation
particularly rapid rotation
extremely rapid rotation
Haumea is the third-brightest Kuiper belt object. Haumea has two moons. Haumea's odd oval shape is probably caused by its extremely rapid rotation. It rotates in just less than 4 hours! Like other Kuiper belt objects, Haumea is covered by ice. Its density is similar to Earth’s Moon, at 2.6 – 3.3 g/cm 3 . This means tha...
A changing magnetic field produces an electric current in what?
substance
matter
organ
a conductor
Law stating that a changing magnetic field produces an electric current in a conductor.
What do plants do to prevent water loss at night?
open their petals
close their stems
shed their petals
close their leaves
Plants also detect and respond to the daily cycle of light and darkness. For example, some plants open their leaves during the day to collect sunlight and then close their leaves at night to prevent water loss. Environmental stimuli that indicate changing seasons trigger other responses. Many plants respond to the days...
What term describes a colloidal dispersion of a liquid in either a liquid or a solid?
compound
mix
suspension
emulsion
An emulsion is a colloidal dispersion of a liquid in either a liquid or a solid.
What evidence is there that mt. everest was once at the bottom of a sea?
glaciers
skulls
corals
fossils
Fossils of ocean animals are found at the top of Mt. Everest. Mt. Everest is the highest mountain on Earth. These fossils show that the area was once at the bottom of a sea. The seabed was later uplifted to form the Himalaya mountain range. An example is shown in the Figure below .
Because atoms have equal numbers of positive protons and negative electrons, what kind of electric charge do they possess?
negative
none
positive
neutral
Atoms have equal numbers of positive protons and negative electrons, so they are neutral in electric charge.
What is the term for interactions between individuals of different species over an extended period of time which impact the abundance and distribution of the associating populations?
food chain
parasitic relationships
cooperative evolution
symbiotic relationships
Symbiosis Symbiotic relationships, or symbioses (plural), are close interactions between individuals of different species over an extended period of time which impact the abundance and distribution of the associating populations. Most scientists accept this definition, but some restrict the term to only those species t...
Plane mirrors work because the light rays create what behind the mirror?
a virtual example
a mirror image
a entire image
a virtual image
The sketch below shows how we see an image in a plane mirror. Plane mirrors work because the light rays create a virtual image behind the mirror. Light rays from the object strike the mirror and reflect according to the law of reflection. When some of the light rays enter our eye, our eye and brain interpret these rays...
What do we call natural resources that are remade by natural processes as quickly as people use them?
geothermal
nonrenewable
exotic
renewable
Renewable resources are natural resources that are remade by natural processes as quickly as people use them. Examples of renewable resources include sunlight and wind. They are in no danger of being used up. Metals and some other minerals are considered renewable as well because they are not destroyed when they are us...
What is the process of breaking down food into components the body can absorb called?
excretion
absorption
filtration
digestion
The digestive system has three main functions: digestion of food, absorption of nutrients, and elimination of solid food waste. Digestion is the process of breaking down food into components the body can absorb. It consists of two types of processes: mechanical digestion and chemical digestion.
What controls what moves inside and outside the cell?
mitochondria
nucleus
golgi apparatus
the plasma membrane
The plasma membrane controls what moves inside and outside the cell.
Yeasts are single-celled fungi. about 1,000 species are recognized, but the most common species is saccharomyces cerevisiae, which is used in this?
potatoes making
cookie making
cake making
bread making
Opening Essay Although yeast has been used for thousands of years, its true nature has been known only for the last two centuries. Yeasts are single-celled fungi. About 1,000 species are recognized, but the most common species is Saccharomyces cerevisiae, which is used in bread making. Other species are used for the fe...
Another measure of the effectiveness of a machine is its what?
chemical advantage
aesthetic effect
cost benefit
mechanical advantage
Another measure of the effectiveness of a machine is its mechanical advantage. Mechanical advantage is the number of times a machine multiplies the input force. It can be calculated with the equation:.
What are biofilms resistant to many common forms of?
assimilation
vaccination
termination
sterilization
planktonic counterparts. Overall, biofilms are very difficult to destroy because they are resistant to many common forms of sterilization.
Fractures and faults are terms you hear when talking about?
magnets
volcanoes
storms
earthquakes
Compare fractures and faults and define how they are related to earthquakes.
What are resources that can not be remade, or would take too long to remake to keep up wiht human use called?
photoreactive resources
renewable resources
green resources
nonrewable resources
Nonrenewable resources are natural resources that can’t be remade or else take too long to remake to keep up with human use. Examples of nonrenewable resources are coal, oil, and natural gas, all of which are fossil fuels. Fossil fuels form from the remains of plants and animals over hundreds of millions of years. We a...
Alkenes with the same atoms but different shapes are called what?
isotopes
alcohols
monomers
isomers
Alkenes can have different shapes. They can form straight chains, branched chains, or rings. Alkenes with the same atoms but different shapes are called isomers. Smaller alkenes have relatively high boiling and melting points, so they are gases at room temperature. Larger alkenes have lower boiling and melting points, ...
Which of the animals digest cellulose with the aid of methanogens?
goats
pigs
apes
cows
Stuart Chalmers. Cows digest cellulose with the aid of methanogens . CC BY 2.0.
What is the major source of warmth for earth?
equator
the Moon
seasons
the sun
Earth is warmed by energy that radiates from the sun. Earth radiates some of the energy back into space. Greenhouse gases (GHGs) trap much of the re-radiated energy, causing an increase in the temperature of the atmosphere close to the surface.
Like a runner passing a baton, the transmission of nerve impulses between neurons depends on what?
receptors
enzymes
axons
neurotransmitters
The transmission of nerve impulses between neurons is like the passing of a baton between runners in a relay race. After the first runner races, she passes the baton to the second runner. Then the second runner takes over. Instead of a baton, a neuron passes neurotransmitters to the next neuron.
Which organ is the control center of the nervous system?
the lungs
the heart
the spine
the brain
What weighs about three pounds and contains up to 100 billion cells? The answer is the human brain. The brain is the control center of the nervous system. It’s like the pilot of a plane. It tells other parts of the nervous system what to do.
Continental climates are generally found in what areas of landmasses?
wetlands
northerly
buttes
inland
Farther inland, the climate is influenced by cold or hot air from the land. This air may be dry, because it comes from over land. An inland climate is usually more extreme. Winters may be very cold, and summers may be very hot. Precipitation can be low. This is a continental climate .
What mainly gives the body energy?
fuel
water
sunlight
food
Food gives the body energy. You need energy for everything you do. The energy in food is measured in a unit called the Calorie.
A mineral can be made of an element or a?
cell
Sediment
component
compound
A mineral is a solid material that forms by a natural process. A mineral can be made of an element or a compound. It has a specific chemical composition that is different from other minerals. One mineral's physical properties differ from others'. These properties include crystal structure, hardness, density and color. ...
Herbivores are heterotrophs that eat only or mainly what?
fish
decayed matter
animals
plants
Many mammals are herbivores. Herbivores are heterotrophs that eat only or mainly plant foods (or algae). Depending on the species of mammals, they may eat leaves, shoots, stems, roots, seeds, nuts, fruits, flowers, and/or grasses. Some mammals even eat conifer needles or tree bark. Mammals that are herbivores include r...
The heart is an organ in which system?
respiratory system
nervous system
immune system
circulatory system
Human organs are organized into organ systems. An organ system is a group of organs that work together to carry out a complex function. Each organ of the system does part of the overall job. For example, the heart is an organ in the circulatory system. The circulatory system also includes the blood vessels and blood. T...
What are the subatomic particles of the nucleus called?
protons
cores
eukaryotes
nucleons
Summary Subatomic particles of the nucleus (protons and neutrons) are called nucleons. Anuclide is an atom with a particular number of protons and neutrons. An unstable nucleus that decays spontaneously is radioactive, and its emissions are collectively called radioactivity. Isotopes that emit radiation are Saylor URL:...
Who wrote the book, on the origin of species?
shaw
Scopes
Sagan
darwin
In his book On the Origin of Species , Darwin included a lot of evidence for evolution. Since then, much more evidence has accumulated. The evidence includes millions of fossils, like the one in Figure below . It also includes detailed knowledge of living organisms.
Tar sands are rocky materials mixed with what?
magma
shale
coal
very thick oil
Tar sands are rocky materials mixed with very thick oil. The tar is too thick to pump, and so tar sands are strip-mined. Hot water and caustic soda are used to separate the oil from the rock. This creates a slurry, which is shaken. The oil floats to the top and is skimmed off.
A current in a circuit needs a complete what?
stream
cause
speed
path
Electromagnetic waves generally propagate out from a source in all directions, sometimes forming a complex radiation pattern. A linear antenna like this one will not radiate parallel to its length, for example. The wave is shown in one direction from the antenna in Figure 24.7 to illustrate its basic characteristics. I...
How do glucose, ions, and other larger molecules leave the blood?
through veinous fissures
through cell membranes
through capillary tips
through intercellular clefts
20.3 | Capillary Exchange By the end of this section, you will be able to: • Identify the primary mechanisms of capillary exchange • Distinguish between capillary hydrostatic pressure and blood colloid osmotic pressure, explaining the contribution of each to net filtration pressure • Compare filtration and reabsorption...
The basal forebrain contains what that are important in learning and memory?
atoms
oxygen
ribosomes
nuclei
Many of the higher neurological functions, such as memory, emotion, and consciousness, are the result of cerebral function. The complexity of the cerebrum is different across vertebrate species. The cerebrum of the most primitive vertebrates is not much more than the connection for the sense of smell. In mammals, the c...
What thin layer of air acts as a barrier to prevent cool air from mixing with warm air in the stratosphere?
liposphere
methosphere
endosphere
tropopause
At the top of the troposphere is a thin layer of air called the tropopause. You can see it in Figure above . This layer acts as a barrier. It prevents cool air in the troposphere from mixing with warm air in the stratosphere.
What is the name for the male gamete?
egg
ova
chromatid
sperm
The strength of acids is measured on what scale?
μg
Killalot
qcd
ph
The strength of acids is measured on the pH scale. A pH value less than 7 indicates an acid, and the lower the number is, the stronger the acid.
What term is also known as the contact activation pathway?
identical pathway
central pathway
internal pathway
intrinsic pathway
Intrinsic Pathway The intrinsic pathway (also known as the contact activation pathway) is longer and more complex. In this case, the factors involved are intrinsic to (present within) the bloodstream. The pathway can be prompted by damage to the tissues, resulting from internal factors such as arterial disease; however...
What comprises the contents of a cell between the plasma membrane and the nuclear envelope?
cytoskeleton
protoplasm
cerebellum
cytoplasm
The Cytoplasm The cytoplasm comprises the contents of a cell between the plasma membrane and the nuclear envelope (a structure to be discussed shortly). It is made up of organelles suspended in the gel-like cytosol, the cytoskeleton, and various chemicals (Figure 3.7). Even though the cytoplasm consists of 70 to 80 per...
What is used to convert concentrations to collisions per second?
particles factor
speeds factor
collision meter
frequency factor
The frequency factor is used to convert concentrations to collisions per second. Equation 14.39 is known as the Arrhenius equation and summarizes the collision model of chemical kinetics, where T is the absolute temperature (in K) and R is the ideal gas constant [8.314 J/(K·mol)]. Ea indicates the sensitivity of the re...
The ovules, which are the female gametophytes, are held in what organ?
uterus
abdomen
testes
ovary
The ovary holds the ovules , the female gametophytes. When the ovules are fertilized, the ovule becomes the seed and the ovary becomes the fruit.
Snippet 2: one of the reasons the periodic table is so useful is because its structure allows us to qualitatively determine how some properties of the elements vary versus their position on the periodic table. the variation of properties versus position on the periodic table is called what?
acoustic trends
chemical trends
gravity trends
periodic trends
One of the reasons the periodic table is so useful is because its structure allows us to qualitatively determine how some properties of the elements vary versus their position on the periodic table. The variation of properties versus position on the periodic table is called periodic trends. There is no other tool in sc...
Equilibriums are affected by changes in concentration, total pressure or volume, and this?
rate
time
oxygen
temperature
Equilibriums are affected by changes in concentration, total pressure or volume, and temperature.
What type of seed-bearing structure of a flowering plant usually develop into?
Apple
Stem
food
fruit
Development of Fruit and Fruit Types After fertilization, the ovary of the flower usually develops into the fruit. Fruits are usually associated with having a sweet taste; however, not all fruits are sweet. Botanically, the term “fruit” is used for a ripened ovary. In most cases, flowers in which fertilization has take...
What are ionic substances completely held together by?
magnetic bonds
thermal bonds
localized bonds
ionic bonds
Ionic substances are completely held together by ionic bonds. The full charges of the ions (for example, Na + and Cl - in sodium chloride) cause electrostatic interactions that result in a stable crystal lattice. We saw in the previous chapter that most ionic compounds have high melting points, are brittle, are often s...
What word do get from the arabic al-qili, meaning “ashes of the saltwort plant from salt marshes”?
crystals
water
metals
alkali
The elements of group 1 are called the alkali metals. Alkali (from the Arabic al-qili, meaning “ashes of the saltwort plant from salt marshes”) was a general term for substances derived from wood ashes, all of which possessed a bitter taste and were able to neutralize acids. Although oxides of both group 1 and group 2 ...
Metals are elements that can conduct what?
pollution
cycle
orchestras
electricity
Metals are elements that can conduct electricity. Most elements are metals.
The earth is like organisms in that it maintains a stable state, which is also known as what?
dormancy
ketosis
hibernation
homeostasis
Most scientists agree that the Earth itself is not a living thing. However, the Earth does have some aspects of life. Some scientists argue that the Earth maintains homeostasis, a stable state, just like a living organisms.
The purpose of any cooling system is to transfer what type of energy in order to keep things cool?
physical
radiation
atmospheric
thermal
A refrigerator is an example of a cooling system. Another example is an air conditioner. The purpose of any cooling system is to transfer thermal energy in order to keep things cool. A refrigerator, for example, transfers thermal energy from the cool air inside the refrigerator to the warm air in the kitchen. If you’ve...
What is the heart's main task?
split blood cells
make blood
clean blood
pump blood
Tissues may be organized into organs. An organ is a structure composed of two or more types of tissue that work together to do a specific task. For example, the heart is an organ. It consists of muscle, nerve, and other types of tissues. Its task is to pump blood.
Which antibacterial protein is found in tears and saliva?
dopamine
human growth hormone
amino acid
human lysozyme
What elements tend to conduct well?
oils
organics
gases
metals
While many elements differ dramatically in their chemical and physical properties, some elements have similar properties. We can identify sets of elements that exhibit common behaviors. For example, many elements conduct heat and electricity well, whereas others are poor conductors. These properties can be used to sort...
What type of masses are structureless particles that cannot spin?
inertial mass
weightless masses
turning masses
point masses
• Point masses are structureless particles that cannot spin.
What do scientists use to search other planets suitable for living?
microscopes
optics
lasers
telescopes
Scientists are using telescopes to search for other planets that may have conditions favorable for life. The places they can look are near our solar system in our galaxy.
All species of crocodilians have similar body structures, including an elongated snout, powerful jaws, muscular tail, large protective scales, streamlined body, and eyes and nostrils that are positioned on what?
side of head
below the neck
back of head
top of head
The basic crocodilian body plan ( Figure below ) is a very successful one and has changed little over time. Modern species actually look very similar to their Cretaceous ancestors of 84 million years ago. All species of crocodilians have similar body structures, including an elongated snout, powerful jaws, muscular tai...
During adulthood, what is needed for the production of sperm?
androgen
steroids
estrogen
testosterone
During adulthood, testosterone is needed for the production of sperm.
What are solid lipids that animals use to store energy called?
hydrocortisol
steroids
cholesterol
fats
Fats are solid lipids that animals use to store energy.
What in science are very important so that we can compare experimental data from one lab to another and make sure we all are talking about the same thing?
uses measurements
Conventional measurements
available measurements
standard measurements
Standardized measurements make it possible for people everywhere to get the same amount of something. Note the red and white labels on the gas pump above. These labels certify that the gas pump has been checked and is pumping an accurate gallon of gas. Standard measurements in science are very important so that we can ...
What substances in a car battery can be melted and recycled?
steel and sodium
lead and steel
lead and sodium
lead and plastic
Lead is still widely used in car batteries. In recent years, battery recycling is becoming very common - about 98% of car batteries a recycled today. The used batteries go to a processing plant where they are crushed and placed in a tank. The lead sinks to the bottom and can be separated, melted and used again. Plastic...
Unlike a crystalline solid, an amorphous solid is a solid that lacks a what?
color
atoms
weight
ordered internal structure
Unlike a crystalline solid, an amorphous solid is a solid that lacks an ordered internal structure. Some examples of amorphous solids include rubber, plastic, and gels. Glass is a very important amorphous solid that is made by cooling a mixture of materials in such a way that it does not crystallize. Glass is sometimes...
Many carbohydrates can enter glycolysis, most often after conversion to what?
insulin
sucrose
fructose
glucose
If a quantity of a reactant remains unconsumed after complete reaction has occurred, it is?
missing
reduced
static
in excess
The stoichiometry of a reaction describes the relative amounts of reactants and products in a balanced chemical equation. A stoichiometric quantity of a reactant is the amount necessary to react completely with the other reactant(s). If a quantity of a reactant remains unconsumed after complete reaction has occurred, i...
Name the one metal that melts below room temperature?
bronze
aluminum
gold
mercury
Metals have a wide range of melting points, but most are quite high. Only one metal (mercury) melts below room temperature. Others (such as gallium) are solid at room temperature but would melt at body temperature, so they can be melted simply by holding them in your hand. On the other end of the spectrum, tungsten has...
The way a mineral cleaves or fractures depends on what part of the mineral?
the crust
the fault structure
the core
the crystal structure
The way a mineral cleaves or fractures depends on the crystal structure of the mineral.
Ultimately, most life forms get their energy from this?
food
heat
earth
sun
Figure 4.2 Ultimately, most life forms get their energy from the sun. Plants use photosynthesis to capture sunlight, and herbivores eat the plants to obtain energy. Carnivores eat the herbivores, and eventual decomposition of plant and animal material contributes to the nutrient pool.
What was diorite commonly used for in ancient civilizations?
medicine
school
currency
art
An example of a physical model is a drawing of the layers of Earth ( Figure below ). A drawing helps us to understand the structure of the planet. Yet there are many differences between a drawing and the real thing. The size of a model is much smaller, for example. A drawing also doesn’t give good idea of how substance...
Aquatic biomes in the ocean are called what?
artificial biomes
jungle biomes
arid biomes
marine biomes
Aquatic biomes in the ocean are called marine biomes. Organisms that live in marine biomes must be adapted to the salt in the water. For example, many have organs for excreting excess salt. Marine biomes include the oceans, coral reefs, and estuaries ( Figure below ). The oceans are the largest of all the ecosystems. T...
When an ionic compound dissociates in water, water molecules surround each ion and separate it from the rest of the what?
gas
electron shell
mixture
solid
When an ionic compound dissociates in water, water molecules surround each ion and separate it from the rest of the solid. Each ion goes its own way in solution. Saylor URL: http://www. saylor. org/books.
What device is used to measure temperature?
barometer
compass
anemometer
thermometer
A thermometer is a device used to measure temperature. It is placed in contact with an object and allowed to reach thermal equilibrium with the object (they will have the same temperature). The operation of a thermometer is based on some property, such as volume, that varies with temperature. The most common thermomete...
What has the smallest, lightest atoms of all the elements and is colorless, odorless, tasteless and nontoxic, but highly flammable in its pure state?
barium
helium
magnesium
hydrogen
Hydrogen has the smallest, lightest atoms of all elements. Pure hydrogen is a colorless, odorless, tasteless gas that is nontoxic but highly flammable. Hydrogen gas exists mainly as diatomic (“two-atom”) molecules (H 2 ), as shown in the diagram on the right. Hydrogen is the most abundant element in the universe and th...
If two populations do not mate and produce fertile offspring, what results?
small species
same species
large species
separate species
How do you think scientists test whether two populations are separate species? They bring species from two populations back together again. If the two populations do not mate and produce fertile offspring, they are separate species.
What system includes the brain and the spinal cord?
muscular
digestive
lymbic
central nervous
31.2 Central nervous system Central nervous system includes the brain and the spinal cord. Brain There are four lobes of the brain. • • • •.
Light is produced when charged particles do what, frequently in the form of oscillating?
offset
decelerate
increase
accelerate
Light is produced when charged particles accelerate . As a result changing electric and magnetic fields radiate outward. The traveling electric and magnetic fields of an accelerating (often oscillating) charged particle are known as electromagnetic radiation or light.
Respiration rate correlates with what?
pressure
size
heat
energy use
There must be more to this story than just gas exchange with the environment. To begin to appreciate the role of oxygen inside your body, think about when your breathing rate increases: climbing a steep slope, running a race, or skating a shift in a hockey game. Respiration rate correlates with energy use, and that cor...
What is the only commercial way of reproducing plants such as orchids?
grafting
sexual reproduction
cross-breeding
cloning
Birds adapted wings and weathers for flight during what process?
emergence
migration
variation
evolution
Wings and feathers are two adaptations for flight that evolved in birds. Both are clearly displayed in the flying gull in Figure below . Wings evolved from the front limbs of a four-legged ancestor. The wings are controlled by large flight muscles in the chest. Feathers also help birds fly. They provide air resistance ...
Which factor ruins renewable resources like soil and water?
resentful human action
melancholic human action
hateful human action
careless human action
Theoretically, soil and water are renewable resources. However, they may be ruined by careless human actions.
How does the solubility of gases in liquids change with increasing temperature?
no change
it increases
it stabilizes
it decreases
Effect of Temperature on the Solubility of Gases The solubility of gases in liquids decreases with increasing temperature, as shown inFigure 13.10 "Solubilities of Several Common Gases in Water as a Function of Temperature at Partial Pressure of 1 atm". Attractive intermolecular interactions in the gas phase are essent...
What are all living things made of?
muscles
water
proteins
cells
Cells are the tiny building blocks of living things. They couldn’t be discovered until the microscope was invented. The discovery of cells led to the cell theory. This is one of the most important theories in life science.
Where does the nucleus store chromatin ?
xerophyte
chloroplasts
ribosome
nucleoplasm
Figure 4.11 The nucleus stores chromatin (DNA plus proteins) in a gel-like substance called the nucleoplasm. The nucleolus is a condensed region of chromatin where ribosome synthesis occurs. The boundary of the nucleus is called the nuclear envelope. It consists of two phospholipid bilayers: an outer membrane and an in...
What do the liver, gallbladder, and pancreas contribute that aid in digestion?
plasma
contaminants
crystals
chemicals
The liver, gallbladder, and pancreas contribute chemicals that aid in digestion.
What are all tissues external to the vascular cambium called?
larvae
nucleus
membranes
bark
Spirals, spheres, and rods are examples of what distinguishing property of bacteria?
organ
function
color
shape
Bacteria come in many different shapes. Some of the most common shapes are bacilli (rods), cocci (spheres), and spirilli (spirals). Bacteria can be identified and classified by their shape.
The goal of homeostasis is the maintenance of what, around a point or value called a set point?
imbalance
agitation
steadiness
equilibrium
Homeostatic Process The goal of homeostasis is the maintenance of equilibrium around a point or value called a set point. While there are normal fluctuations from the set point, the body’s systems will usually attempt to go back to this point. A change in the internal or external environment is called a stimulus and is...
What type of energy of a system is the sum of the kinetic and potential energies of its atoms and molecules?
deep energy u
external energy u
primary energy u
internal energy u
Internal Energy U We can think about the internal energy of a system in two different but consistent ways. The first is the atomic and molecular view, which examines the system on the atomic and molecular scale. The internal energy U of a system is the sum of the kinetic and potential energies of its atoms and molecule...
Primary batteries are single-use batteries because they cannot be what?
plugged
UP ticked.
refreshed
recharged
Primary Batteries Primary batteries are single-use batteries because they cannot be recharged. A common primary battery is the dry cell (Figure 17.10). The dry cell is a zinc-carbon battery. The zinc can serves as both a container and the negative electrode. The positive electrode is a rod made of carbon that is surrou...
Layers of fat are formed by what type of tissue?
areolar tissue
colchis tissue
trypanosome tissue
adipose tissue
Basidiomycetes do what to wood and other plant material?
evaporate
evolve
revive
decompose
Pathogens infect many animals and are agents of what?
change
drought
mutation
disease
Sediments in oligotrophic lakes contain large amounts of what?
igneous rocks
algae
fertilizer
decomposable organic matter
What tides occur during the new moon and full moon?
bottom
autumn
high
spring
Spring tides occur during the new moon and full moon. The Sun and Moon are in a straight line either on the same side of Earth or on opposite sides. Their gravitational pull combines to cause very high and very low tides. Spring tides have the greatest tidal range.
In passive transport, small molecules or ions move across the cell membrane without requiring input of what?
heating
pressure
water
energy
Passive transport is a way that small molecules or ions move across the cell membrane without input of energy by the cell. The three main kinds of passive transport are diffusion, osmosis, and facilitated diffusion.
Some bacteria also have tail-like structures called what?
nuclei
plasmids
sporangia
flagella
Some bacteria also have tail-like structures called flagella ( Figure below ). Flagella help bacteria move. As the flagella rotate, they spin the bacteria and propel them forward. Though some eukaryotic cells do have a flagella, a flagella in eukaryotes is rare.
People with which skin type run a greater risk of vitamin d deficiency?
weaker skin
lighter skin
brighter skin
darker skin
The epidermis also contains melanocytes , which are cells that produce melanin. Melanin is the brownish pigment that gives skin much of its color. Everyone has about the same number of melanocytes, but the melanocytes of people with darker skin produce more melanin. The amount of melanin produced is determined by hered...
What happens to temperature in the troposphere as the altitude increases?
it stays the same
it increases
it disappears
it decreases
In the troposphere, temperature decreases with altitude. The troposphere gets some of its heat directly from the Sun. Most, however, comes from Earth's surface. The surface is heated by the Sun. Some of that heat radiates back into the air. This makes the temperature higher near the surface than at higher altitudes.
The kidneys help control acid-base balance by excreting _____ and generating bicarbonate that helps maintain blood plasma ph within a normal range?
lithium ions
magnesium ions
sodium ions
hydrogen ions
Buffer Systems in the Body The buffer systems in the human body are extremely efficient, and different systems work at different rates. It takes only seconds for the chemical buffers in the blood to make adjustments to pH. The respiratory tract can adjust the blood pH upward in minutes by exhaling CO2 from the body. Th...
What does the geiger counter detect?
moisture
vibration
convection
radiation
You generally can’t see, smell, taste, hear, or feel radiation. Fortunately, there are devices such as Geiger counters that can detect radiation. A Geiger counter, like the one pictured in the Figure below , contains atoms of a gas that is ionized if it encounters radiation. When this happens, the gas atoms change to i...
Mollusks such as squid and octopi, which must hunt to survive, possess what complex organs containing millions of neurons?
tentacles
gills
hearts
brains
Figure 35.2 Nervous systems vary in structure and complexity. In (a) cnidarians, nerve cells form a decentralized nerve net. In (b) echinoderms, nerve cells are bundled into fibers called nerves. In animals exhibiting bilateral symmetry such as (c) planarians, neurons cluster into an anterior brain that processes infor...
Which direction from the source do pollutants in an aquifer spread?
inward
southward
forward
outward
Pollutants that enter an aquifer spread outward from the source. They spread in the direction the water is moving.