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Within an organism, the cells that give rise to the next generation are known as germ cells, while those that do not (that is, the cells that die when the organism dies) are known as what cells? | cloning | xylem | neural | somatic | reality versus abstraction. It is organisms, whether single- or multi-cellular, that produce new organisms. As we will discuss in detail when we consider the origins of multicellular organisms, a cell within a multicellular organism normally cannot survive outside the organism nor can it produce a new organism - it dep... |
An external opening in the what of amphibians allows wastes and gametes to exit the body? | urethra | anus | oral cavity | cloaca | All amphibians have digestive, excretory, and reproductive systems. All three of these organ systems use a single body cavity, called the cloaca. Wastes enter the cloaca from the digestive and excretory systems. Gametes enter the cloaca from the reproductive system. A single external opening in the cloaca allows the wa... |
What kind of scientists measure percentages of sand, silt, and clay? | petro scientists | texture scientists | amount scientists | soil scientists | Soil scientists measure the percentage of sand, silt, and clay in soil. They plot this information on a triangular diagram, with each type of particle at one corner ( Figure below ). |
What hormone affects developent and maturation in animals? | melatonin | insulin | dopamine | thyroid | |
The three types of mammals are characterized by their method of what? | pattern | specializaiton | differentiation | reproduction | There are three types of mammals, characterized by their method of reproduction. All mammals, except for a few, are viviparous , meaning they produce live young instead of laying eggs. The monotremes , however, have birdlike and reptilian characteristics, such as laying eggs and a cloaca. An example of a monotreme is t... |
What planet has the most volcanoes? | uranus | Mars | Earth | venus | Venus has more volcanoes than any other planet. There are between 100,000 and one million volcanoes on Venus! Most of the volcanoes are now inactive. There are also a large number of craters. This means that Venus doesn’t have tectonic plates. Plate tectonics on Earth erases features over time. Figure below is an image... |
Gene duplications that are able to persist over many generations without causing too much harm to an organism or species can lead to what? | permutations | characteristics | parasites | mutations | |
What keeps earth in orbit around the sun? | momentum | energy | motion | gravity | Why do satellites stay in orbit? Why don't they crash into Earth due to the planet's gravity? Newton’s law of universal gravitation describes what happens. Every object in the universe is attracted to every other object. Gravity makes an apple fall to the ground. Gravity also keeps you from floating away into the sky. ... |
The work-energy theorem states that the net work on a system equals the change in what type of energy? | residual energy | binary energy | new energy | kinetic energy | How the Work-Energy Theorem Applies Now let us consider what form the work-energy theorem takes when both conservative and nonconservative forces act. We will see that the work done by nonconservative forces equals the change in the mechanical energy of a system. As noted in Kinetic Energy and the Work-Energy Theorem, ... |
Living organisms release carbon dioxide into the atmosphere by what method? | major respiration | genomic respiration | widespread respiration | cellular respiration | Cellular respiration by living things releases carbon into the atmosphere or ocean as carbon dioxide. |
Excretory organs that conserve what essential substance help terrestrial animals to avoid desiccation? | food | metabolytes | air | water | |
Venus rotates slowly in a direction opposite to the direction of what? | the sun | the Earth's orbit | the orbit of Mars | its orbit | Venus rotates slowly in a direction opposite to the direction of its orbit. |
What is the ph of pure water? | 2 | 5 | 4 | 7 | milk of magnesia, pH = 10.5 2. pure water, pH = 7 3. wine, pH = 3.0. |
The volume of a gas is comprised of about 10% matter. what is the rest? | normal space | open space | instead space | empty space | The volume of a gas contains only about 10% matter, with the rest being empty space. ΔHsub is equal to ΔHvap. |
Heterotrophs is another name for what group? | producers | omnivores | autotrophs | consumers | Consumers are also called heterotrophs. There are several different types of heterotrophs depending on exactly what they consume. They may be herbivores, carnivores, or omnivores. |
What is dna transcribed into after being replicated? | gene | protein | diploid chromosomes | rna | The three general transfers are believed to occur normally in most cells. These describe the normal flow of biological information. DNA is replicated, DNA is transcribed into RNA, and RNA is translated into protein. The three special transfers are known to occur under special conditions, such as with some viruses. The ... |
What is name of the phenomenon where similar traits evolve independently in species that do not share a common ancestry? | divergent evolution | equation evolution | coalescence evolution | convergent evolution | Figure 22.31 The force on a current-carrying wire in a magnetic field is. |
The flow of water through the sponge is unidirectional, driven by the beating of what? | fin | antennae | cilia | flagella | Sponges are characterized by a feeding system unique among animals. As sponges don't have mouths, they must feed by some other method. Sponges have tiny pores in their outer walls through which water is drawn. Cells in the sponge walls filter food from the water as the water is pumped through the body and out other lar... |
What is the process for developing knowledge called? | creationism | evolution | theory | science | Science is a process for developing knowledge. Change in knowledge about the natural world is expected because there is often room for new observations which may challenge current views. No matter how well one theory explains a set of observations, it is possible that a different theory may explain them just as well or... |
Arteries, veins, and capillaries are the three main types of what? | blood pathways | blood shapes | cell structures | blood vessels | |
Amphibians may attract mates with what? | neither | only calls | only scents | calls or scents | Amphibians may attract mates with calls or scents. |
What type of bounded nucleus do protists have? | Ribosomes | Mitochondrion | Endoplasmic reticulum | membrane | |
Which body part is unsuitable for animals living on land? | hands | lungs | feet | gills | |
Which inducer turns on the expression of the lac genes? | galactose | xerophyte | glucose | allolactose | When lactose is available, a lactose metabolite called allolactose binds to the allosteric site on the repressor. This interaction causes a conformational change in the repressor shape and the repressor falls off the operator, allowing RNA polymerase to bind to the promoter and initiate transcription. Allolactose is ca... |
What is the most common type of brain injury? | Contusion | Diffuse Axonal | Anoxic Event | concussion | The most common type of brain injury is a concussion. This is a bruise on the surface of the brain. It may cause temporary symptoms such as headache and confusion. Most concussions heal on their own in a few days or weeks. However, repeated concussions can lead to permanent changes in the brain. More serious brain inju... |
Changing the shape of an elastic material gives it what type of energy? | initial | thermal | practical | potential | Changing the shape of an elastic material gives it potential energy. |
What type of traits are features that are passed from one generation to the next called? | familial traits | generational traits | genetic traits | inherited traits | The theory of evolution by natural selection means that the inherited traits of a population change over time. Inherited traits are features that are passed from one generation to the next. For example, your eye color is an inherited trait. You inherited your eye color from your parents. Inherited traits are different ... |
What is your body made up of? | energy | skin | millions of elements | trillions of cells | According to the cell theory , all living things are made up of cells, which is the structural unit of living organisms, and living cells always come from other living cells. In fact, each living thing begins life as a single cell. Some living things, such as bacteria, remain single-celled. Other living things, includi... |
Hemoglobin is responsible for transporting what within our blood? | dioxide | water | nitrogen | oxygen | To predict the relative stabilities of metal complexes with different ligands. One of the most important properties of metallic elements is their ability to act as Lewis acids that form complexes with a variety of Lewis bases. A metal complex consists of a central metal atom or ion that is bonded to one or more ligands... |
How do bipedal creatures walk? | on four legs | on twelve legs | on six legs | on two legs | Birds are endothermic tetrapod vertebrates. They are bipedal, which means they walk on two legs. Birds also lay amniotic eggs with hard, calcium carbonate shells. Although birds are the most recent class of vertebrates to evolve, they are now the most numerous vertebrates on Earth. Why have birds been so successful? Wh... |
Any sample of matter that has the same physical and chemical properties throughout the sample is called what? | type | element | molecule | substance | Elements and Compounds Any sample of matter that has the same physical and chemical properties throughout the sample is called a substance. There are two types of substances. A substance that cannot be broken down into chemically simpler components is an element. Aluminum, which is used in soda cans, is an element. A s... |
What is a measure of both speed and direction of motion? | acceleration | distance | intensity | velocity | Velocity is a measure of both speed and direction of motion. Velocity is a vector, which is a measurement that includes both size and direction. |
What do fish eggs hatch to form? | unfertilized eggs | adolescent fish | tadpoles | fish eggs hatch to form larvae | Almost all fish have sexual reproduction, generally with separate sexes. Most fish are oviparous. Many species reproduce by spawning. Eggs hatch to form larvae, which undergo metamorphosis to become adults. |
Commensalism, mutualism, and parasitism are known as what type of relationships? | various | simple | peculiar | symbiotic | 19.4 Community Ecology Communities include all the different species living in a given area. The variety of these species is referred to as biodiversity. Many organisms have developed defenses against predation and herbivory, including mechanical defenses, warning coloration, and mimicry. Two species cannot exist indef... |
The modern model of the atom, which scientists call the quantum mechanical model, is based on what scientist's work on orbitals? | Newton | Sagan | Bohr | schrödinger | Schrödinger’s work on orbitals is the basis of the modern model of the atom, which scientists call the quantum mechanical model. The modern model is also commonly called the electron cloud model. That’s because each orbital around the nucleus of the atom resembles a fuzzy cloud around the nucleus, like the ones shown i... |
Time, mass, length, and temperature are considered to be what kinds of units? | unitary | support | measurement | base | Base units have independent scales and cannot be described by a combination of any other base units. Examples of base units used in chemistry are length, mass, temperature, and time. |
What does the heat energy affect in the atmosphere? | density and humidity | gravity and precipitation | erosion and condensation | winds and weather | How do the differences in energy striking different latitudes affect Earth? The planet is much warmer at the equator than at the poles. In the atmosphere, the differences in heat energy cause winds and weather. On the surface, the differences cause ocean currents. Can you explain how?. |
What are the taste receptors found as tiny bumps on the tongue called? | hard buds | ear buds | fat buds | taste buds | Taste receptors are found in tiny bumps on the tongue called taste buds (see Figure below ). There are separate taste receptors for sweet, salty, sour, bitter, and meaty tastes. The meaty taste is called umami . You can learn more about taste receptors and the sense of taste by watching the animation at the following l... |
What is the chemical formula for a glucose molecule? | d5 h12 o6 | a5 h12 o6 | H2 C3 NA6 | c6 h12 o6 | The sugar glucose is a covalent compound. When sugar dissolves in water, it forms individual glucose molecules (C 6 H 12 O 6 ). You can see how this happens in the Figure below . Sugar is polar like water, so sugar molecules also have positive and negative ends. Forces of attraction between oppositely charged ends of w... |
In physics, the number of waves that pass a fixed point in a given amount time is referred to as what ? | creation frequency | combination frequency | wave count | wave frequency | Wave speed is related to both wavelength and wave frequency. Wavelength is the distance between two corresponding points on adjacent waves. Wave frequency is the number of waves that pass a fixed point in a given amount of time. This equation shows how the three factors are related:. |
The reactions between alkali metals and water are particularly vigorous and include the rapid production of large quantities of what gas? | carbon | helium | oxygen | hydrogen | All alkali metals are very soft and can be cut easily with a knife. Due to their high reactivity, they must be stored under oil to prevent them from reacting with oxygen or water vapor in the air. The reactions between alkali metals and water are particularly vigorous and include the rapid production of large quantitie... |
Batteries produce voltage through what type of reaction? | thermal | magnetic | radiation | chemical | Chemical cells are found in batteries. They produce voltage by means of chemical reactions. A chemical cell has two electrodes, which are strips made of different materials, such as zinc and carbon (see Figure below ). The electrodes are suspended in an electrolyte. An electrolyte is a substance containing free ions th... |
The speed of a particle in what state is directly proportional to the temperature of the system? | liquid | frozen | solid | gas | The speed of a gas particle is directly proportional to the temperature of the system. |
Acne results from a blockage of sebaceous glands by what? | fat | mucous | progesterone | sebum | Chapter 5 1 The epidermis provides protection, the dermis provides support and flexibility, and the hypodermis (fat layer) provides insulation and padding. 3 Figure 5.6 These cells have desmosomes, which give the cells their spiny appearance. 5 D 7 C 9 C 11 D 13 B 15 A 17 C 19 C 21 C 23 B 25 The pigment melanin, produc... |
Just as millions of different words are spelled with our 26-letter english alphabet, millions of different proteins are made with the 20 common what? | enzymes | mutation acids | peptides | amino acids | Just as millions of different words are spelled with our 26-letter English alphabet, millions of different proteins are made with the 20 common amino acids. However, just as the English alphabet can be used to write gibberish, amino acids can be put together in the wrong sequence to produce nonfunctional proteins. Alth... |
Anaerobic respiration takes place without what? | carbon | nitrogen | movement | oxygen | Aerobic respiration , which takes place in the presence of oxygen, evolved after oxygen was added to Earth’s atmosphere. This type of respiration is useful today because the atmosphere is now 21% oxygen. However, some anaerobic organisms that evolved before the atmosphere contained oxygen have survived to the present. ... |
Which other planet in the solar system is the easiest to observe from earth? | Jupiter | Pluto | Mercury | mars | Mars is the easiest planet to observe. As a result, it has been studied more than any other planet besides Earth. People can stand on Earth and observe the planet through a telescope. We have also sent many space probes to Mars. In April 2011, there were three scientific satellites in orbit around Mars. The rover, Oppo... |
What is in the inside of your mouth and nose instead of skin? | cuticle layer | scales | gums | mucous membranes | The mouth and nose are not lined with skin. Instead, they are lined with mucous membranes . Other organs that are exposed to the outside world, including the lungs and stomach, are also lined with mucous membranes. Mucous membranes are not tough like skin, but they have other defenses. |
While matter is recycled, ecosystems need a constant input of what? | light | heating | food | energy | In all biomes, ecosystems need a constant input of energy. Matter, on the other hand, is constantly recycled in ecosystems. |
What is term for the smallest particle of an element that still has the properties of said element? | molecule | proton | nucleus | atom | Atoms are the building blocks of matter. They are the smallest particles of an element that still have the element’s properties. Elements, in turn, are pure substances—such as nickel, hydrogen, and helium—that make up all kinds of matter. All the atoms of a given element are identical in that they have the same number ... |
What is the protein that carries iron that binds with oxygen in red blood cells? | insulin | keratin | potassium | hemoglobin | The trillions of red blood cells in blood plasma carry oxygen. Red blood cells contain hemoglobin , a protein with iron that binds with oxygen. Red blood cells are made in the marrow of long bones, rib bones, the skull, and the vertebrae. These cells survive for about 120 days, and then they are destroyed. Mature red b... |
What branch of science is based on the modern atomic theory, which states that all matter is composed of atoms? | biology | physics | psychology | chemistry | Chemistry is based on the modern atomic theory, which states that all matter is composed of atoms. |
Why do sharks sense low levels of electricity? | to reproduce | to locate mates | to sleep | to locate prey | Fish also have a centralized nervous system with a brain. Fish brains are small compared with the brains of other vertebrates, but they are large and complex compared with the brains of invertebrates. Fish also have highly developed sense organs that allow them to see, hear, feel, smell, and taste. Sharks and some othe... |
What membrane is populated by two types of photosystems that cooperate in the light reactions of photosynthesis? | subcutaneous | choroid | chloroplasts | thylakoid | |
At what point can nutrients enter or exit an ecosystem? | Hottest Point | Largest Population Point | Longest Point | any point | Nutrients can enter or exit an ecosystem at any point and can cycle around the planet. |
B cells and t cells are examples of what type of cells? | skin cells | heart cells | cancer cells | white blood cells | There are two different types of specific immune responses. One type involves B cells. The other type involves T cells. Recall that B cells and T cells are types of white blood cells that are key in the immune response. Whereas the immune system's first and second line of defense are more generalized or non-specific, t... |
There are three different types of rna. all three types are needed to make what? | Blood | acids | lipids | proteins | There are three different types of RNA. All three types are needed to make proteins. |
Niche and habitat are concepts related to what broader term? | community | population | biome | ecosystem | 7. Compare and contrast the ecosystem concepts of niche and habitat. |
What do opposite charges do to one another? | repel | strengthen | weaken | attract | Opposite charges attract, and like charges repel. |
What is the name for the sinking of the dense, salty seawater in cold climates? | tidal activity | cyclones | jet stream | downwelling | Water becomes more dense when it is colder and when it has more salt. In the North Atlantic Ocean, cold winds chill the water at the surface. Sea ice grows in this cold water, but ice is created from fresh water. The salt is left behind in the seawater. This cold, salty water is very dense, so it sinks to the bottom of... |
When gas particles heat up and gain energy, what do they do? | move slower | go up | stop | move faster | When gas particles heat up and gain energy, they move faster. This increases their collisions with each other and their container, causing greater pressure. |
Ion pumps, the biological machines responsible for the selective transport of metal ions, are complex assemblies of what? | acids | cells | minerals | proteins | Ion Transport The Na+, K+, Mg2+, and Ca2+ ions are important components of intracellular and extracellular fluids. Both Na+ and Ca2+ are found primarily in extracellular fluids, such as blood plasma, whereas K + and Mg2+ are found primarily in intracellular fluids. Substantial inputs of energy are required to establish... |
Lack of proper food over a period of time can lead to what condition, where the body is not getting enough nutrients to grow and stay healthy? | bulimia | anemia | mortality | malnutrition | Refusing one meal won't stunt your growth. But lack of proper food over a period of time can lead to malnutrition. That means, the body is not getting enough nutrients to grow and stay healthy. Kids who are malnourished may not grow as tall as they would otherwise. |
Two water molecules contain 4 hydrogen atoms and how many oxygen atoms? | 6 | 1 | 4 | 2 | Two water molecules contain 4 hydrogen atoms and 2 oxygen atoms. A mole of water molecules contains 2 moles of hydrogen atoms and 1 mole of oxygen atoms. |
The carrying angle is larger in females to accommodate their what? | cranium | broader shoulders | narrower pelvis | wider pelvis | the ulna and radius bones. The small, rounded area that forms the distal end is the head of the ulna. Projecting from the posterior side of the ulnar head is the styloid process of the ulna, a short bony projection. This serves as an attachment point for a connective tissue structure that unites the distal ends of the ... |
Examples of organ systems in a human include the skeletal, nervous, and what? | immune systems | affecting systems | nervous systems | reproductive systems | Organ system : Group of organs that work together to perform a certain function. Examples of organ systems in a human include the skeletal, nervous, and reproductive systems. |
Most hormones are controlled by what type of feedback, which causes the hormone to decrease its own production? | unusual | positive | neutral | negative | Most hormones are controlled by negative feedback in which the hormone feeds back to decrease its own production. This type of feedback brings things back to normal whenever they start to become too extreme. Positive feedback is much less common because it causes conditions to become increasingly extreme. |
What is the stage called for babies that are in the first year of life after birth? | adolescence | original stage | primary stage | infancy | Infancy is the first year of life after birth. Infants are born with a surprising range of abilities. For example, they have well-developed senses of touch, hearing, and smell. They can also communicate their needs by crying. During their first year, they develop many other abilities, including those described below. F... |
What forms a barrier between the cytoplasm and the environment outside the cell? | cell wall | cuticle | epidermis | plasma membrane | The plasma membrane forms a barrier between the cytoplasm and the environment outside the cell. The plasma membrane has selective permeability. |
Over time, what changes solid rock into pieces? | leaching | metamorphosis | creep | weathering | Weathering changes solid rock into pieces. These pieces are called sediments. Sediments are described in the chapter Earth's Materials and Crust . Sediments are different sizes of rock particles. Boulders are sediments; so is gravel. At the other end, silt and clay are also sediments. Weathering may also cause the mine... |
Eukaryotic cells undergo what kinds of divisions that more primitive cells do not? | homologous | budding | meiosis | mitosis | Mitosis , or division of the nucleus, occurs only in eukaryotic cells. By the time mitosis occurs, the cell’s DNA has already replicated. Mitosis occurs in four phases, called prophase, metaphase, anaphase, and telophase. You can see what happens in each phase in Figure below . The phases are described below. You can a... |
The orbicularis oris is a circular muscle that moves the lips, and the orbicularis oculi is a circular muscle that does what? | moisturizes the eye | pressure the eye | opens the eye | closes the eye | The orbicularis oris is a circular muscle that moves the lips, and the orbicularis oculi is a circular muscle that closes the eye. The occipitofrontalis muscle moves up the scalp and eyebrows. The muscle has a frontal belly and an occipital (near the occipital bone on the posterior part of the skull) belly. In other wo... |
What may have developed to help our ancestors distinguish between ripe and unripe fruits? | night vision | fine motor skills | acute hearing | color vision | McKay Savage. Color vision may have developed to help our ancestors distinguish between ripe and unripe fruits . CC BY 2.0. |
Which stage is specialized for dispersal & reproduction? | cocoon stage | fetal stage | larval stage | adult stage | |
What three parameters do seismographs measure? | trouble , length and distance | height, width and distance | aging , length and distance | strength, length and distance | Seismograms contain a lot of information about an earthquake: its strength, length and distance. Wave height used to determine the magnitude of the earthquake. The seismogram shows the different arrival times of the seismic waves ( Figure below ). The first waves are P-waves since they are the fastest. S-waves come in ... |
What topographic feature does a circle with inward hatches represent on a contour map? | a mountain | a lake | vegetation | a depression | On a contour map, a circle with inward hatches indicates a depression. |
Which temperatures cause particles of reactants to have more energy? | lower | non-existant | reducing | higher | When the temperature of reactants is higher, the rate of the reaction is faster. At higher temperatures, particles of reactants have more energy, so they move faster. They are more likely to bump into one another and to collide with greater force. For example, when you fry an egg, turning up the heat causes the egg to ... |
Not all cells of a leaf carry out photosynthesis. cells within the middle layer of a leaf have chloroplasts, which contain the photosynthetic what? | wires | pipes | structure | apparatus | Figure 5.7 Not all cells of a leaf carry out photosynthesis. Cells within the middle layer of a leaf have chloroplasts, which contain the photosynthetic apparatus. (credit "leaf": modification of work by Cory Zanker). |
What is the advantage of selecting for certain genetic traits for crops? | Faster growth | protection from pests | improves taste | promotes productivity | Improving crops by selecting for certain genetic traits. The desired traits promote productivity. Recently, genetically engineered crops have been introduced. |
What is given off from plants and taken in by animals? | nitrogen | methane | sulfur | oxygen | |
What is the simplest unit that has the fundamental chemical properties of an element? | cell | neutron | nucleus | atom | Covalent Molecules and Compounds Just as an atom is the simplest unit that has the fundamental chemical properties of an element, a molecule is the simplest unit that has the fundamental chemical properties of a covalent compound. Some pure elements exist as covalent molecules. Hydrogen, nitrogen, oxygen, and the halog... |
Bacteria are what kind of cell? | eukaryotes | protists | blood | prokaryotes | The rod-shaped organisms in Figure below are bacteria called Salmonella . Bacteria (bacterium, singular) are prokaryotes in the Bacteria Domain. The word Salmonella may sound familiar. That's because Salmonella is a common cause of food poisoning. Many other types of bacteria also cause human diseases. But not all bact... |
What is the first stage of cellular respiration? | decarboxylation | gluconeogenesis | Krebs cycle | glycolysis | The first stage of cellular respiration is glycolysis. It does not require oxygen. |
Who study volcanoes to be able to predict when a volcano will erupt? | ornithologists | vocologists | virologists | volcanologists | Volcanic eruptions can be devastating, particularly to the people who live close to volcanoes. Volcanologists study volcanoes to be able to predict when a volcano will erupt. Many changes happen when a volcano is about to erupt. |
What is the term for electric current that keeps reversing direction? | magnetic current | direct current | AC/DC | alternating current | The Figure below shows the direction of the current that is generated by a moving magnet. If the magnet is moved back and forth repeatedly, the current keeps changing direction. In other words, alternating current (AC) is produced. Alternating current is electric current that keeps reversing direction. |
How many alleles comes from each parent? | three | none | two | one | When gametes unite during fertilization, the resulting zygote inherits two alleles for each gene. One allele comes from each parent. |
How close a measurement is to the correct value for that measurement is known as what? | temperature | frequency | rate | accuracy | Accuracy and Precision of a Measurement Science is based on observation and experiment—that is, on measurements. Accuracy is how close a measurement is to the correct value for that measurement. For example, let us say that you are measuring the length of standard computer paper. The packaging in which you purchased th... |
What pigment is required for photosynthesis to occur? | xanthophyll | carotene | chroma | chlorophyll | |
What begins approximately six weeks after fertilization in an embryo? | incubation | calcification | elongation | ossification | Development of Bone Ossification, or osteogenesis, is the process of bone formation by osteoblasts. Ossification is distinct from the process of calcification; whereas calcification takes place during the ossification of bones, it can also occur in other tissues. Ossification begins approximately six weeks after fertil... |
What do you call the energy that must be overcome in order for a chemical reaction to occur, or the minimum energy required to start a chemical reaction? | kinetic energy | expression energy | phase energy | activation energy | Regardless of whether reactions are exothermic reactions or endothermic reactions , they all need energy to get started. This energy is called activation energy . Activation energy is like the push you need to start moving down a slide. The push gives you enough energy to start moving. Once you start, you keep moving w... |
Frogs and toads, salamanders and newts, and caecilians are the three orders of what group of animals? | mammals | marsupials | reptiles | amphibians | There are about 6,200 known species of living amphibians. They are classified into three orders: frogs and toads, salamanders and newts, and caecilians. |
What are vesicles made of? | filaments | cells | membranes | phospholipids | A vesicle. Because vesicles are made of phospholipids, they can break off of and fuse with other membraneous material. This allows them to serve as small transport containers, moving substances around the cell and to the cell membrane. |
Deoxyribonucleic acid (dna) is nucleotide that stores what type of information? | variation | mononucleus | mutation | genetic | Nucleic Acids The nucleic acids differ in their type of pentose sugar. Deoxyribonucleic acid (DNA) is nucleotide that stores genetic information. DNA contains deoxyribose (so-called because it has one less atom of oxygen than ribose) plus one phosphate group and one nitrogen-containing base. The “choices” of base for D... |
What two basic types of feather does a bird have? | flight and landing | carrying and down | up and down | flight and down | Feathers help birds fly and also provide insulation and serve other purposes. Birds actually have two basic types of feathers: flight feathers and down feathers. Both are shown in Figure below . Flight feathers are long, stiff and waterproof. They provide lift and air resistance without adding weight. Down feathers are... |
Which fuels provide most of the world’s energy? | artificial fuels | coal fuels | pattern fuels | fossil fuels | Figure below shows the mix of energy resources used worldwide in 2006. Fossil fuels still provide most of the world’s energy, with oil being the single most commonly used energy resource. Natural gas is used less than the other two fossil fuels, but even natural gas is used more than all renewable energy resources comb... |
The cathode and anode collectively are the electrodes of what? | photo cell | circuit cell | switch cell | voltaic cell | One application of redox reactions requires that they be physically separated. Even though the two half reactions are physically separated, a spontaneous redox reaction still occurs. However, in this case, the electrons transfer through the wire connecting the two half reactions; that is, this setup becomes a source of... |
What part of the sweet potato store sugar from photosynthesis as starch? | shrubs | plants | skin | roots | Secondary growth of sweet potato roots provides more space to store food. Roots store sugar from photosynthesis as starch. What other starchy roots do people eat?. |
What is the ratio of charge on a capacitor to potential difference across it called? | resonance | velocity | electromagnetism | capacitance | When a capacitor is placed in a circuit, current does not actually travel across it. Rather, equal and opposite charge begins to build up on opposite sides of the capacitor --- mimicking a current --- until the electric field in the capacitor creates a potential difference across it that balances the voltage drop acros... |
What substances that primarily comprise plasma membranes form a bilayer? | steroids | amino acids | enzymes | phospholipids | Plasma membranes are primarily made up of phospholipids (orange). The hydrophilic ("water-loving") head and two hydrophobic ("water-hating") tails are shown. The phospholipids form a bilayer (two layers). The middle of the bilayer is an area without water. There can be water on either side of the bilayer. There are man... |
What type of friction is friction that acts on objects when they are sliding over a surface? | rolling friction | spreading friction | static friction | sliding friction | Sliding friction is friction that acts on objects when they are sliding over a surface. Sliding friction is weaker than static friction. That’s why it’s easier to slide a piece of furniture over the floor after you start it moving than it is to get it moving in the first place. Sliding friction can be useful. For examp... |
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