questions stringlengths 37 1.22k | reasoning stringlengths 0 3.56k ⌀ | answers stringlengths 4 138 |
|---|---|---|
What form of energy is light?
Here are the choices:
A. seismic
B. electromagnetic
C. hydro
D. mechanical | B: electromagnetic. | |
What is a common chemical substance on planet earth?
Here are the choices:
A. nitrogen
B. hydrogen
C. oxygen
D. water | Water is a common chemical substance on planet Earth. In fact, Earth is sometimes called the "water planet" because almost 75% of its surface is covered with water. If you look at Figure below , you will see where Earth’s water is found. The term water generally refers to its liquid state, and water is a liquid over a wide range of temperatures on Earth. However, water also occurs on Earth as a solid (ice) and as a gas (water vapor). | D: water. |
Blood calcium levels are tightly regulated by the what system?
Here are the choices:
A. nervous
B. cardiovascular
C. digestive
D. endocrine | Of course, calcium is critical for many other biological processes. It is a second messenger in many signaling pathways, and is essential for muscle contraction, nerve impulse transmission, and blood clotting. Given these roles, it is not surprising that blood calcium levels are tightly regulated by the endocrine system. The organs involved in the regulation are the parathyroid glands. | D: endocrine. |
This bodily defense function attacks pathogens and includes inflammatory response and phagocytosis?
Here are the choices:
A. vomitting
B. first line of defense
C. third line of defense
D. second line of defense | The second line of defense attacks pathogens that manage to enter the body. It includes the inflammatory response and phagocytosis by nonspecific leukocytes. | D: second line of defense. |
Lodgepole cones remain closed until exposed to what?
Here are the choices:
A. extreme heat
B. predators
C. UV light
D. precipitation | A: extreme heat. | |
What is the change of state from a gas to a liquid?
Here are the choices:
A. condensation
B. fermentation
C. combustion
D. vaporation | A puddle of water left undisturbed eventually disappears. The liquid molecules escape into the gas phase, becoming water vapor. Vaporization is the process in which a liquid is converted to a gas. Evaporation is the conversion of a liquid to its vapor below the boiling temperature of the liquid. If the water is instead kept in a closed container, the water vapor molecules do not have a chance to escape into the surroundings and so the water level does not change. As some water molecules become vapor, an equal number of water vapor molecules condense back into the liquid state. Condensation is the change of state from a gas to a liquid. | A: condensation. |
The steropodon may have been an ancestor of which animal?
Here are the choices:
A. geckos
B. wooly mammoth
C. platypus
D. lioness | The first monotremes may have evolved about 150 million years ago. Early monotreme fossils have been found in Australia. An example is a genus called Steropodon , shown in Figure below . It may have been the ancestor of the platypus. Early monotremes retained some of the traits of their therapsid ancestors. For example, they laid eggs and had a cloaca. These traits are still found in modern monotremes. | C: platypus. |
Closely associated with "work", what is characterized by its many forms and the fact that it is conserved?
Here are the choices:
A. heating
B. energy
C. matter
D. fuel | Introduction to Work, Energy, and Energy Resources Energy plays an essential role both in everyday events and in scientific phenomena. You can no doubt name many forms of energy, from that provided by our foods, to the energy we use to run our cars, to the sunlight that warms us on the beach. You can also cite examples of what people call energy that may not be scientific, such as someone having an energetic personality. Not only does energy have many interesting forms, it is involved in almost all phenomena, and is one of the most important concepts of physics. What makes it even more important is that the total amount of energy in the universe is constant. Energy can change forms, but it cannot appear from nothing or disappear without a trace. Energy is thus one of a handful of physical quantities that we say is conserved. Conservation of energy (as physicists like to call the principle that energy can neither be created nor destroyed) is based on experiment. Even as scientists discovered new forms of energy, conservation of energy has always been found to apply. Perhaps the most dramatic example of this was supplied by Einstein when he suggested that mass is equivalent to energy (his famous equation E = mc 2 ). From a societal viewpoint, energy is one of the major building blocks of modern civilization. Energy resources are key limiting factors to economic growth. The world use of energy resources, especially oil, continues to grow, with ominous consequences economically, socially, politically, and environmentally. We will briefly examine the world’s energy use patterns at the end of this chapter. There is no simple, yet accurate, scientific definition for energy. Energy is characterized by its many forms and the fact that it is conserved. We can loosely define energy as the ability to do work, admitting that in some circumstances not all energy is available to do work. Because of the association of energy with work, we begin the chapter with a discussion of work. Work is intimately related to energy and how energy moves from one system to another or changes form. | B: energy. |
What is the time it takes for radioactive substance to decay?
Here are the choices:
A. decay rate
B. full-life
C. half-life
D. deterioration rate | The disintegration of unstable nuclei does not occur all at once. The rate of disintegration is a statistical process. The most convenient way to consider it is by a concept known as half-life . The time required for half of the atoms in any given quantity of a radioactive substance to decay is the half-life of that element. Each particular isotope has its own half-life. For example, the half-life of radium-226 is 1600 years. That is, beginning with 1.00 gram of radium-226, it would take 1600 years for half of it to decay and leave 0.50 gram remaining. After another 1600 years, only 0.25 gram would remain. In each half-life, exactly half of the beginning amount decays. | C: half-life. |
What type of biomes are found in the salt water of the ocean?
Here are the choices:
A. marine
B. major
C. surreal
D. active | Marine biomes are found in the salt water of the ocean. | A: marine. |
What is formed when an enzyme binds its substrate?
Here are the choices:
A. vessel - substrate complex
B. lock and key model
C. enzyme - substrate complex
D. nucleus - substrate complex | View an animation (http://openstaxcollege. org/l/hexokinase2) of induced fit. When an enzyme binds its substrate, an enzyme-substrate complex is formed. This complex lowers the activation energy of the reaction and promotes its rapid progression in one of multiple possible ways. On a basic level, enzymes promote chemical reactions that involve more than one substrate by bringing the substrates together in an optimal orientation for reaction. Another way in which enzymes promote the reaction of their substrates is by creating an optimal environment within the active site for the reaction to occur. The chemical properties that emerge from the particular arrangement of amino acid R groups within an active site create the perfect environment for an enzyme’s specific substrates to react. The enzyme-substrate complex can also lower activation energy by compromising the bond structure so that it is easier to break. Finally, enzymes can also lower activation energies by taking part in the chemical reaction itself. In these cases, it is important to remember that the enzyme will always return to its original state by the completion of the reaction. One of the hallmark properties of enzymes is that they remain ultimately unchanged by the reactions they catalyze. After an enzyme has catalyzed a reaction, it releases its product(s) and can catalyze a new reaction. | C: enzyme - substrate complex. |
What type of rock is a sandstone?
Here are the choices:
A. landform rocks
B. limestone rocks
C. igneous rocks
D. sedimentary rocks | If you look up close, you would be able to see grains of sand. From this distance, you can see different layers from where the sand was laid down. This rock is sandstone. The sand grains are cemented together to make sandstone. Sandstone is a common type of sedimentary rock. | D: sedimentary rocks. |
Which acids provide the molecular blueprints for all proteins produced in living systems?
Here are the choices:
A. nucleic acids
B. periodic acids
C. amino acids
D. nitrous acids | The final type of biomolecules that we will be looking at are the nucleic acids. Like carbohydrates and proteins, nucleic acids are complex polymers of a few simple building blocks. Nucleic acids provide the molecular blueprints for all proteins produced in living systems. We will explore the process by which this information is translated into functional structures later in this lesson. First, we will look at the structures of nucleic acids. | A: nucleic acids. |
Cephalopods have three hearts that pump blood of what color?
Here are the choices:
A. Green
B. Red
C. blue
D. purple | Cephalopods include the octopus and squid. They have a prominent head and a well-developed brain. Typically the foot has been modified into a set of arms or tentacles. Members of this class can change color. They can also change texture and body shape, and, and if those camouflage techniques don't work, they can still "disappear" in a cloud of ink. Cephalopods have three hearts that pump blue blood, they're jet powered by their muscular foot, and they're found in all oceans of the world. Cephalopods are thought to be the most intelligent of invertebrates. They have eyes and other senses that rival those of humans. Many cephalopods are active and efficient predators. What features do you think allows for this?. | C: blue. |
Influenza is a type of what, where glycoproteins attach to a host epithelial cell?
Here are the choices:
A. atoms disease
B. recent disease
C. nucleus disease
D. viral disease | Figure 17.6 In influenza virus infection, glycoproteins attach to a host epithelial cell. As a result, the virus is engulfed. RNA and proteins are made and assembled into new virions. | D: viral disease. |
What is the smallest aromatic hydrocarbon?
Here are the choices:
A. anthracene
B. benzene
C. naphthalene
D. phenanthrene | Benzene is the smallest aromatic hydrocarbon. It has just one ring. You can see its structural formula in Figure below . Benzene has many uses. For example, it is used in air fresheners and mothballs because of its strong scent. | B: benzene. |
A hypothesis is scientific only if it can be tested by what?
Here are the choices:
A. making a conclusion
B. independent variable
C. carbon dating
D. making observations | For a hypothesis to be testable means that it is possible to make observations that agree or disagree with it. If a hypothesis cannot be tested by making observations, it is not scientific. Consider this statement:. | D: making observations. |
Aging occurs as cells lose their ability to do what?
Here are the choices:
A. fold
B. duplicate
C. divide
D. split | Aging occurs as cells lose their ability to divide. | C: divide. |
The tyndall effect refers to the scattering of what by colloidal particles?
Here are the choices:
A. primary colors
B. dust mites
C. visible light
D. dark matter | The Tyndall effect is the scattering of visible light by colloidal particles. | C: visible light. |
Acids are associated with a low number on which scale?
Here are the choices:
A. ionic
B. acidic
C. metric
D. ph | As indicated in http://catalog. flatworldknowledge. com/bookhub/reader/2547 - gob-ch10_s04, weak acids are relatively common, even in the foods we eat. But we occasionally come across a strong acid or base, such as stomach acid, that has a strongly acidic pH of 1–2. By definition, strong acids and bases can produce a relatively large amount of hydrogen or hydroxide ions and, as a consequence, have a marked chemical activity. In addition, very small amounts of strong acids and bases can change the pH of a solution very quickly. If 1 mL of stomach acid [which we will approximate as 0.05 M HCl(aq)] is added to the bloodstream, and if no correcting mechanism is present, the pH of the blood would go from about 7.4 to about 4.9—a pH that is not conducive to continued living. Fortunately, the body has a mechanism for minimizing such dramatic pH changes. The mechanism involves a buffer, a solution that resists dramatic changes in pH. Buffers do so by being composed of certain pairs of solutes: either a weak acid plus a salt derived from that weak acid or a weak base plus a salt of that weak base. For example, a buffer can be composed of dissolved acetic acid (HC2H3O2, a weak acid) and sodium acetate (NaC2H3O2, a salt derived from that acid). Another example of a buffer is a solution containing ammonia (NH3, a weak base) and ammonium chloride (NH4Cl, a salt derived from that base). Let us use an acetic acid–sodium acetate buffer to demonstrate how buffers work. If a strong base—a source of OH−(aq) ions—is added to the buffer solution, those hydroxide ions will react with the acetic acid in an acid-base reaction: HC2H3O2(aq) + OH−(aq) → H2O(ℓ) + C2H3O2−(aq) Rather than changing the pH dramatically by making the solution basic, the added hydroxide ions react to make water, and the pH does not change much. | D: ph. |
Said to go hand-in-hand with science, what evolves as new materials, designs, and processes are invented?
Here are the choices:
A. technology
B. biology
C. invention
D. industry | Technology evolves as new materials, designs, and processes are invented. | A: technology. |
What are the poles labeled?
Here are the choices:
A. north and south
B. east and west
C. west and south
D. southwest and south | A: north and south. | |
What is considered to be the "fundamental unit" of life?
Here are the choices:
A. bacteria
B. organ
C. cell
D. proton | It could easily be said that a cell is the fundamental unit of life, the smallest unit capable of life or the structural and functional unit necessary for life. But whatever it is, a cell is necessary for life. This concept will discuss some of the fundamental properties of the cell with lessons that include the cell structure, transport in and out of the cell and cell communication. | C: cell. |
What two states of matter are included in the category "fluids"?
Here are the choices:
A. liquids and soilds
B. liquids and gases
C. bacteria and gases
D. solids and gases | Fluid friction is friction that acts on objects that are moving through a fluid. A fluid is a substance that can flow and take the shape of its container. Fluids include liquids and gases. If you’ve ever tried to push your open hand through the water in a tub or pool, then you’ve experienced fluid friction between your hand and the water. When a skydiver is falling toward Earth with a parachute, fluid friction between the parachute and the air slows the descent (see Figure below ). Fluid pressure with the air is called air resistance. The faster or larger a moving object is, the greater is the fluid friction resisting its motion. The very large surface area of a parachute, for example, has greater air resistance than a skydiver’s body. | B: liquids and gases. |
When matter changes into an entirely different substance with different chemical properties, what has occurred?
Here are the choices:
A. chemical change
B. physical change
C. mechanical change
D. gaseous change | A chemical change occurs whenever matter changes into an entirely different substance with different chemical properties. A chemical change is also called a chemical reaction. Many complex chemical changes occur to produce the explosions of fireworks. An example of a simpler chemical change is the burning of methane. Methane is the main component of natural gas, which is burned in many home furnaces. During burning, methane combines with oxygen in the air to produce entirely different chemical substances, including the gases carbon dioxide and water vapor. You can watch some very colorful chemical changes occurring in the video at this URL:. | A: chemical change. |
Phospholipids are unable to mix with what?
Here are the choices:
A. air
B. nitrogen
C. solids
D. water | Molecules in the cell membrane allow it to be semipermeable. The membrane is made of a double layer of phospholipids (a "bilayer") and proteins ( Figure below ). Recall that phospholipids, being lipids, do not mix with water. It is this quality that allows them to form the outside barrier of the cell. | D: water. |
What are molecules that the immune system recognize as foreign to the body?
Here are the choices:
A. viruses
B. peptides
C. antigens
D. tumors | The average kinetic energy of atoms (each of mass and average speed ) in a gas is related to the temperature of the gas, measured in Kelvin. The Boltzmann constant is a constant of nature, equal to. | C: antigens. |
The end result of diffusion is an equal concentration, or equilibrium , of molecules on both sides of what?
Here are the choices:
A. the organelle
B. the membrane
C. the cell
D. the organism | Diffusion will continue until the concentration gradient has been eliminated. Since diffusion moves materials from an area of higher concentration to the lower, it is described as moving solutes "down the concentration gradient. " The end result of diffusion is an equal concentration, or equilibrium , of molecules on both sides of the membrane. At equilibrium, movement of molecules does not stop. At equilibrium, there is equal movement of materials in both directions. | B: the membrane. |
What paired organs that are part of the urinary system play the prime role in excretion?
Here are the choices:
A. lungs
B. kidneys
C. ovaries
D. liver | Each of the above organs of excretion is also part of another body system. For example, the large intestine and liver are part of the digestive system, and the lungs are part of the respiratory system. The kidneys are the main organs of excretion. They are part of the urinary system. | B: kidneys. |
The fungus benefits from the constant supply of food produced by what?
Here are the choices:
A. the photosynthesizer
B. the host
C. the phytoflagellate
D. the spermatophyte | A lichen is a mutualistic relationship between a fungus and a photosynthetic organism. The other organism is usually a cyanobacterium or green alga. The fungus grows around the bacterial or algal cells. The fungus benefits from the constant supply of food produced by the photosynthesizer. The photosynthesizer benefits from the water and nutrients absorbed by the fungus. Figure below shows lichen growing on a rock. | A: the photosynthesizer. |
Gases can be classifed as real or what?
Here are the choices:
A. noble
B. shape
C. ideal
D. dense | Did you notice that none of these statements relates to the identity of the gas? This means that all gases should behave similarly. A gas that follows these statements perfectly is called an ideal gas. Most gases show slight deviations from these statements and are called real gases. However, the existence of real gases does not diminish the importance of the kinetic theory of gases. One of the statements of the kinetic theory mentions collisions. As gas particles are constantly moving, they are also constantly colliding with each other and with the walls of their container. There are forces involved as gas particles bounce off the container walls (Figure 8.9 "Gas Pressure"). The force generated by gas particles divided by the. | C: ideal. |
What is a mutation?
Here are the choices:
A. change in the nucleotide sequence of dna
B. change in the swetha sequence of dna
C. change in the distinct sequence of dna
D. change in the rna sequence of dna | 28.7 Patterns of Inheritance There are two aspects to a person’s genetic makeup. Their genotype refers to the genetic makeup of the chromosomes found in all their cells and the alleles that are passed down from their parents. Their phenotype is the expression of that genotype, based on the interaction of the paired alleles, as well as how environmental conditions affect that expression. Working with pea plants, Mendel discovered that the factors that account for different traits in parents are discretely transmitted to offspring in pairs, one from each parent. He articulated the principles of random segregation and independent assortment to account for the inheritance patterns he observed. Mendel’s factors are genes, with differing variants being referred to as alleles and those alleles being dominant or recessive in expression. Each parent passes one allele for every gene on to offspring, and offspring are equally likely to inherit any combination of allele pairs. When Mendel crossed heterozygous individuals, he repeatedly found a 3:1 dominant–recessive ratio. He correctly postulated that the expression of the recessive trait was masked in heterozygotes but would resurface in their offspring in a predictable manner. Human genetics focuses on identifying different alleles and understanding how they express themselves. Medical researchers are especially interested in the identification of inheritance patterns for genetic disorders, which provides the means to estimate the risk that a given couple’s offspring will inherit a genetic disease or disorder. Patterns of inheritance in humans include autosomal dominance and recessiveness, X-linked dominance and recessiveness, incomplete dominance, codominance, and lethality. A change in the nucleotide sequence of DNA, which may or may not manifest in a phenotype, is called a mutation. | A: change in the nucleotide sequence of dna. |
What are biological catalysts that speeds up biochemical reactions?
Here are the choices:
A. enzymes
B. carbohydrates
C. hormones
D. proteins | This super fast train can obviously reach great speeds. And there's a lot of technology that helps this train go fast. Speaking of helping things go fast brings us to enzymes. Life could not exist without enzymes. Essentially, enzymes are biological catalysts that speed up biochemical reactions. | A: enzymes. |
What type of reaction is a transfer of a proton from one molecule or ion to another?
Here are the choices:
A. ionic bonding
B. thermal reaction
C. acid-base
D. ionization | An acid-base reaction according to the Brønsted-Lowry definition is a transfer of a proton from one molecule or ion to another. When ammonia is dissolved in water, it undergoes the following reversible reaction. | C: acid-base. |
What part of the plant, in general, is responsible for transport and storage of water and minerals?
Here are the choices:
A. petals
B. pistil
C. leaves
D. stems | Stems are needed for transport and storage. Their vascular tissue carries water and minerals from roots to leaves. It carries dissolved sugar from the leaves to the rest of the plant. Without this connection between roots and leaves, plants could not survive high above the ground in the air. In many plants, ground tissue in stems also stores food or water during cold or dry seasons. | D: stems. |
One gram of carbohydrates provides how many calories of energy?
Here are the choices:
A. one
B. eight
C. two
D. four | Carbohydrates include sugars, starches, and fiber. Sugars and starches are used by the body for energy. One gram of carbohydrates provides 4 Calories of energy. Fiber, which is found in plant foods, cannot be digested but is needed for good health. | D: four. |
Mushrooms and other fungi obtain energy from what?
Here are the choices:
A. the soil
B. the sun
C. the air
D. other organisms | Mushrooms and other fungi obtain energy from other organisms. That’s why you often see fungi growing on a fallen tree; the rotting tree is their source of energy ( Figure below ). | D: other organisms. |
How are protozoa that cause giardiasis spread?
Here are the choices:
A. insects
B. starch and water
C. food and water
D. lakes and rivers | Protozoa that cause giardiasis are spread by contaminated food or water. They live inside the intestine. They may cause abdominal pain, fever, and diarrhea. | C: food and water. |
What can prevent the passage of molecules and ions between cells, such as in the blood-brain barrier?
Here are the choices:
A. solid junctions
B. tight junctions
C. special junctions
D. fatty junctions | In addition to holding cells together, tight junctions play a role in the transport of materials. Tight junctions prevent the passage of molecules and ions through the space between cells. So these molecules and ions must actually enter cells (either by diffusion or active transport) in order to proceed through a tissue. This allows tight junctions to indirectly play a role over what substances are allowed into a specific cell. Tight junctions play this role in maintaining the blood-brain barrier. | B: tight junctions. |
Give an example of air pollution while painting indoors.
Here are the choices:
A. variety fumes
B. gas fumes
C. fuel fumes
D. paint fumes | If you are painting indoors, there are more important concerns than just getting messy. You should also be concerned about breathing in the fumes from the paints. Making sure to get plenty of fresh air while painting is very important. Paint fumes can have serious health effects. Paint fumes are just one example of indoor air pollution. | D: paint fumes. |
What plays a variety of important roles in biochemical systems?
Here are the choices:
A. bacteria
B. mutation
C. reactants
D. protein | Proteins play a variety of important roles in biochemical systems. Some of the most common protein functions are listed below:. | D: protein. |
What type of plants grow on other plants?
Here are the choices:
A. legumes
B. epiphytes
C. parasites
D. bryophytes | Plants called epiphytes grow on other plants. They obtain moisture from the air and make food by photosynthesis. Most epiphytes are ferns or orchids that live in tropical or temperate rainforests (see Figure below ). Host trees provide support, allowing epiphyte plants to obtain air and sunlight high above the forest floor. Being elevated above the ground lets epiphytes get out of the shadows on the forest floor so they can get enough sunlight for photosynthesis. Being elevated may also reduce the risk of being eaten by herbivores and increase the chance of pollination by wind. | B: epiphytes. |
What provides a protective covering for the body and helps maintain homeostasis?
Here are the choices:
A. unadorned system
B. lysogenic system
C. endorcrine system
D. integumentary system | Because the organs of the integumentary system are external to the body, you may think of them as little more than “accessories,” like clothing or jewelry. But the organs of the integumentary system serve important biological functions. They provide a protective covering for the body and help the body maintain homeostasis. | D: integumentary system. |
Uranium is an important part of the process used to harness which type of power?
Here are the choices:
A. gravitational
B. wind
C. solar
D. nuclear | Nuclear Fuels Nuclear fuel consists of a fissionable isotope, such as uranium-235, which must be present in sufficient quantity to provide a self-sustaining chain reaction. In the United States, uranium ores contain from 0.05–0.3% of the uranium oxide U3O8; the uranium in the ore is about 99.3% nonfissionable U-238 with only 0.7% fissionable U-235. Nuclear reactors require a fuel with a higher concentration of U-235 than is found in nature; it is normally enriched to have about 5% of uranium mass as U-235. At this concentration, it is not possible to achieve the supercritical mass necessary for a nuclear explosion. Uranium can be enriched by gaseous diffusion (the only method currently used in the US), using a gas centrifuge, or by laser separation. In the gaseous diffusion enrichment plant where U-235 fuel is prepared, UF6 (uranium hexafluoride) gas at low pressure moves through barriers that have holes just barely large enough for UF6 to pass through. The slightly lighter 235UF6 molecules diffuse through the barrier slightly faster than the heavier 238UF6 molecules. This process is repeated through hundreds of barriers, gradually increasing the concentration of 235UF6 to the level needed by the nuclear reactor. The basis for this process, Graham’s law, is described in the chapter on gases. The enriched UF6 gas is collected, cooled until it solidifies, and then taken to a fabrication facility where it is made into fuel assemblies. Each fuel assembly consists of fuel rods that contain many thimble-sized, ceramic-encased, enriched uranium (usually UO2) fuel pellets. Modern nuclear reactors may contain as many as 10 million fuel pellets. The amount of energy in each of these pellets is equal to that in almost a ton of coal or 150 gallons of oil. | D: nuclear. |
Budding and fission in annelids are examples of what type of reproduction?
Here are the choices:
A. sexual
B. hybrid
C. byproduct
D. asexual | Most annelids can reproduce both asexually and sexually. Asexual reproduction may occur by budding or fission. Sexual reproduction varies by species. Some species go through a larval stage before developing into adults. Other species grow to adult size without going through a larval stage. | D: asexual. |
What is the process by which plants make their own food?
Here are the choices:
A. mitochondrial process
B. respiration
C. ATP cycle
D. photosynthesis | D: photosynthesis. | |
In what part of the carbon cycle does carbon move between living things and the air?
Here are the choices:
A. biotic cycle
B. endothermic cycle
C. abdaspac cycle
D. envelop cycle | Carbon moves through ecosystems in two cycles that overlap. In the biotic cycle, it moves between living things and the air. In the abiotic cycle, it moves between the air, ground, and oceans. By burning fossil fuels, humans have increased the amount of carbon dioxide in the air. | A: biotic cycle. |
Herbivores and the bacteria that live in their intestines demonstrate a two-way beneficial relationship called what?
Here are the choices:
A. parasitism
B. pragmatism
C. syncretism
D. mutualism | An example of a mutualistic relationship is between herbivores (plant-eaters) and the bacteria that live in their intestines. The bacteria get a place to live. Meanwhile, the bacteria help the herbivore digest food. Both species benefit, so this is a mutualistic relationship. The clownfish and the sea anemones also have a mutualistic relationship. The clownfish protects the anemone from anemone-eating fish, and the stinging tentacles of the anemone protect the clownfish from predators ( Figure below ). Another example of this type of symbiotic relationship is the relationship between the plover bird and the African crocodile. The tiny blackbird acts as a toothpick for the fierce crocodile, and helps by removing tiny morsels of food that are stuck between the crocodile's teeth. These food remains are the source of food for the bird. Another example is between the ostrich and the zebra. The ostrich always moves with the herd of zebras since it has a poor sense of hearing and smell, whereas the zebra has very sharp senses. The ostrich has a keen sense of sight, which the zebra lacks. Hence, these two species depend on each other to warn one another of any nearby imposing dangers. | D: mutualism. |
What joins within each testis to form the epididymis?
Here are the choices:
A. viviparous tubules
B. seminiferous tubules
C. hypodermic tubules
D. interstitial tubules | The seminiferous tubules within each testis join to form the epididymis. The epididymis (plural, epididymes) is a coiled tube about 6 meters (20 feet) long lying atop the testis inside the scrotum. The functions of the epididymis are to mature and store mature sperm until they leave the body. | B: seminiferous tubules. |
How many layers of phospholipids does the cell membrane contain?
Here are the choices:
A. five
B. three
C. four
D. two | The cell membrane consists of two layers of phospholipids. It encloses the cytoplasm and controls what enters and leaves the cell. | D: two. |
What process within cells makes sure that every gamete receives a copy of every chromosome?
Here are the choices:
A. genomes
B. meiosis
C. fission
D. mutations | All of our cells contain DNA. Meiosis ensures that each gamete receives a copy of each chromosome. | B: meiosis. |
Do amphibians and reptiles maintain a constant body temperature?
Here are the choices:
A. no, they have a lower body temperature than their surroundings
B. no, they have about the same body temperature as their surroundings
C. no, they have a higher body temperature than their surroundings
D. yes | The following figures summarize the basic features of major terrestrial biomes. Think about how its biodiversity and types of plants and animals relate to its climate. For example, why do you think there are no amphibians or reptiles in tundra biomes? (Hint: Amphibians and reptiles cannot maintain a constant body temperature. Instead, they have about the same temperature as their surroundings. ). | B: no, they have about the same body temperature as their surroundings. |
Most vascular plants are seed plants, also known as?
Here are the choices:
A. fungus
B. bacteria
C. spermatophytes
D. sporozoans | Most vascular plants are seed plants, or spermatophytes. They reproduce with seeds and pollen. Some modern seed plants are gymnosperms that produce seeds in cones. | C: spermatophytes. |
Centrifuges use what to perform their task?
Here are the choices:
A. absorption
B. magnetism
C. jets
D. inertia | Figure 6.17 Centrifuges use inertia to perform their task. Particles in the fluid sediment come out because their inertia carries them away from the center of rotation. The large angular velocity of the centrifuge quickens the sedimentation. Ultimately, the particles will come into contact with the test tube walls, which will then supply the centripetal force needed to make them move in a circle of constant radius. | D: inertia. |
What are the two unique features of mollusks?
Here are the choices:
A. mantle and radula
B. antennae and pseudopod
C. pseudopod and mantle
D. radula and antennae | Two unique features of mollusks are the mantle and radula (see Figure above ). The mantle is a layer of tissue that lies between the shell and the body. It secretes calcium carbonate to form the shell. It forms a cavity, called the mantle cavity , between the mantle and the body. The mantle cavity pumps water for filter feeding. The radula is a feeding organ with teeth made of chitin. It is located in front of the mouth in the head region. Herbivorous mollusks use the radula to scrape food such as algae off rocks. Predatory mollusks use the radula to drill holes in the shells of their prey. | A: mantle and radula. |
Name the two types of water turtles live in.
Here are the choices:
A. ocean water and sea water
B. ocean water and fresh water
C. arctic water and ice water
D. river water and lake water | Many turtles are aquatic. They may live in the ocean or in fresh water. Other turtles are terrestrial and live on land. All lizards are terrestrial. Their habitats may range from deserts to rainforests. They may live in a range of places, from underground burrows to the tops of trees. Most snakes are terrestrial, but some are aquatic. Crocodilians live in and around swamps or bodies of water. The water may be fresh or salty, depending on the species of crocodilian. | B: ocean water and fresh water. |
What structures are located on roof of the nasopharynx and on each side of the pharynx?
Here are the choices:
A. testicles
B. uvula
C. tonsils
D. tongues | Figure 21.10 Locations and Histology of the Tonsils (a) The pharyngeal tonsil is located on the roof of the posterior superior wall of the nasopharynx. The palatine tonsils lay on each side of the pharynx. (b) A micrograph shows the palatine tonsil tissue. LM × 40. (Micrograph provided by the Regents of the University of Michigan Medical School © 2012). | C: tonsils. |
What colorful arc-shaped atmospheric phenomena are produced by a combination of refraction and reflection?
Here are the choices:
A. sunsets
B. shadows
C. lightning
D. rainbows | Rainbows are produced by a combination of refraction and reflection. You may have noticed that you see a rainbow only when you look away from the sun. Light enters a drop of water and is reflected from the back of the drop, as shown in Figure 25.24. The light is refracted both as it enters and as it leaves the drop. Since the index of refraction of water varies with wavelength, the light is dispersed, and a rainbow is observed, as shown in Figure 25.25 (a). (There is no dispersion caused by reflection at the back surface, since the law of reflection does not depend on wavelength. ) The actual rainbow of colors seen by an observer depends on the myriad of rays being refracted and reflected toward the observer’s eyes from numerous drops of water. The effect is most spectacular when the background is dark, as in stormy weather, but can also be observed in waterfalls and lawn sprinklers. The arc of a rainbow comes from the need to be looking at a specific angle relative to the direction of the sun, as illustrated in Figure 25.25 (b). (If there are two reflections of light within the water drop, another “secondary” rainbow is produced. This rare event produces an arc that lies above the primary rainbow arc—see Figure 25.25 (c). ) Rainbows Rainbows are produced by a combination of refraction and reflection. | D: rainbows. |
Rabies transmission occurs when saliva from an infected mammal enters a wound. the virus travels through neurons in the peripheral nervous system to the central nervous system where it impairs this?
Here are the choices:
A. skeletal system
B. brain function
C. reproduction system
D. lung function | Figure 21.5 Viruses are classified based on their core genetic material and capsid design. (a) Rabies virus has a single-stranded RNA (ssRNA) core and an enveloped helical capsid, whereas (b) variola virus, the causative agent of smallpox, has a double-stranded DNA (dsDNA) core and a complex capsid. Rabies transmission occurs when saliva from an infected mammal enters a wound. The virus travels through neurons in the peripheral nervous system to the central nervous system where it impairs brain function, and then travels to other tissues. The virus can infect any mammal, and most die within weeks of infection. Smallpox is a human virus transmitted by inhalation of the variola virus, localized in the skin, mouth, and throat, which causes a characteristic rash. Before its eradication in 1979, infection resulted in a 30–35 percent mortality rate. (credit “rabies diagram”: modification of work by CDC; “rabies micrograph”: modification of work by Dr. Fred Murphy, CDC; credit “small pox micrograph”: modification of work by Dr. Fred Murphy, Sylvia Whitfield, CDC; credit “smallpox photo”: modification of work by CDC; scale-bar data from Matt Russell). | B: brain function. |
Newton realized that the nature of gravity on earth that pulls an apple to the ground could explain the motion of these?
Here are the choices:
A. molecules
B. moon and planets
C. seasons
D. atoms and quarks | As has been noted in numerous Things Great and Small vignettes, this is not the first time the large has been explained by the small and vice versa. Newton realized that the nature of gravity on Earth that pulls an apple to the ground could explain the motion of the moon and planets so much farther away. Minute atoms and molecules explain the chemistry of substances on a much larger scale. Decays of tiny nuclei explain the hot interior of the Earth. Fusion of nuclei likewise explains the energy of stars. Today, the patterns in particle physics seem to be explaining the evolution and character of the universe. And the nature of the universe has implications for unexplored regions of particle physics. Cosmology is the study of the character and evolution of the universe. What are the major characteristics of the universe as we know them today? First, there are approximately 10 11 galaxies in the observable part of the universe. An average galaxy contains more than 10 11 stars, with our Milky Way galaxy being larger than average, both in its number of stars and its dimensions. Ours is a spiral-shaped galaxy with a diameter of about 100,000 light years and a thickness of about 2000 light years in the arms with a central bulge about 10,000 light years across. The Sun lies about 30,000 light years from the center near the galactic plane. There are significant clouds of gas, and there is a halo of less-dense regions of stars surrounding the main body. (See Figure 34.3. ) Evidence strongly suggests the existence of a large amount of additional matter in galaxies that does not produce light—the mysterious dark matter we shall later discuss. | B: moon and planets. |
Where do most of the steps of cellular respiration take place?
Here are the choices:
A. cytoplasm
B. nucleus
C. mitochondria
D. ribosomes | Most of the steps of cellular respiration take place in the mitochondria. | C: mitochondria. |
Which metal is not solid at room temperature?
Here are the choices:
A. titanium
B. aluminum
C. silver
D. mercury | All metals except for mercury are solids at room temperature. Many metals are shiny, ductile, and malleable. Most are also good conductors of heat. | D: mercury. |
Induced mutations are caused by environmental factors. what term is used to describe a mutation that has no environmental cause?
Here are the choices:
A. cancerous mutation
B. evident mutation
C. numerous mutation
D. spontaneous mutation | Mutagenesis may occur spontaneously or be induced. A spontaneous mutation can just happen. These mutations are not caused by an environmental factor, but occur during normal cellular processes. A spontaneous mutation may be due to a mistake during DNA replication or transcription. Mutations may also occur during mitosis and meiosis. A mutation caused by an environmental factor, or mutagen , is known as an induced mutation . Typical mutagens include chemicals, like those inhaled while smoking, and radiation, such as X-rays, ultraviolet light, and nuclear radiation. Table below lists some spontaneous mutations that are common. | D: spontaneous mutation. |
What part of the cell does cellular respiration occur?
Here are the choices:
A. nuclei
B. proton
C. mitochondria
D. glucose | Cellular respiration occurs in the mitochondria. Figure 20.13 "Respiration" shows the mitochondrion’s two membranes: outer andinner. The inner membrane is extensively folded into a series of internal ridges calledcristae. Thus there are two compartments in mitochondria: the intermembrane space, which lies between the membranes, and the matrix, which lies inside the inner membrane. | C: mitochondria. |
How is the chance of survival affected when animals lack parental care?
Here are the choices:
A. variable
B. decreased
C. increased
D. unaffected | B: decreased. | |
Elements with magic numbers of what tend to have more stable isotopes?
Here are the choices:
A. pressure
B. nucleus
C. molecules
D. protons | Isotopes with magic numbers of protons and/or neutrons tend to be especially stable. Elements with magic numbers of protons tend to have more stable isotopes than elements that do not. | D: protons. |
What is the term for the steep sloped side of a sand dune?
Here are the choices:
A. front face
B. break face
C. slide face
D. slip face | A sand dune has a gentle slope on the side the wind blows from. The opposite side has a steep slope. This side is called the slip face. | D: slip face. |
Pulleys are generally used to do what with objects?
Here are the choices:
A. pack
B. wrap
C. clean
D. lift | A pulley is a simple machine that consists of a rope and grooved wheel. The rope fits into the groove in the wheel, and pulling on the rope turns the wheel. Pulleys are generally used to lift objects, especially heavy objects. The object lifted by a pulley is called the load. The force applied to the pulley is called the effort. | D: lift. |
What term describes how close estimates are to one another?
Here are the choices:
A. precision
B. efficiency
C. precise
D. Distant | Precision describes how close estimates are to one another. Estimates that are relatively close to one another are precise. Let’s assume that ten different students made an estimate of the volume shown in Figure above , and the values were: 52.9, 52.8, 52.9, 52.9, 53.3, 52.0, 52.8, 52.9, 53.0, 52.8. We can determine how precise these data by analyzing how close they are to an average. The average could be the mean, median or mode. The most common understanding of the average is the mean. This value is calculated by adding up all the numbers and then dividing by the total number of values. Other terms that can refer to the average are the median and the mode. The median is the middle value in a numerically ordered list of numbers. The mode is the value that occurs most often in a set of numbers. If no number is repeated, there is no mode for the list. Here are the calculated averages:. | A: precision. |
What are membrane-bound organelles that can have secretory, excretory, and storage functions?
Here are the choices:
A. prokaryotes
B. vacuoles
C. alleles
D. nuclei | Vacuoles are membrane-bound organelles that can have secretory, excretory, and storage functions. Many organisms will use vacuoles as storage areas and some plant cells have very large vacuoles. Vesicles are much smaller than vacuoles and function in transporting materials both within and to the outside of the cell. | B: vacuoles. |
The structural classification of joints divides them into bony, fibrous, cartilaginous, and synovial joints. the bones of fibrous joints are held together by fibrous connective tissue; the three types of fibrous joints are sutures, syndesomes, and what?
Here are the choices:
A. gomphoses
B. articular
C. synchondrosis
D. cartilaginous | 38.3 Joints and Skeletal Movement The structural classification of joints divides them into bony, fibrous, cartilaginous, and synovial joints. The bones of fibrous joints are held together by fibrous connective tissue; the three types of fibrous joints are sutures, syndesomes, and gomphoses. Cartilaginous joints are joints in which the bones are connected by cartilage; the two types of cartilaginous joints are synchondroses and symphyses. Synovial joints are joints that have a space between the adjoining bones. The functional classification divides joints into three categories: synarthroses, amphiarthroses, and diarthroses. The movement of synovial joints can be classified as one of four different types: gliding, angular, rotational, or special movement. Gliding movements occur as relatively flat bone surfaces move past each other. Angular movements are produced when the angle between the bones of a joint changes. Rotational movement is the movement of a bone as it rotates around its own longitudinal axis. Special movements include inversion, eversion, protraction, retraction, elevation, depression, dorsiflexion, plantar flexion, supination, pronation, and opposition. Synovial joints are also classified into six different categories on the basis of the shape and structure of the joint: planar, hinge, pivot, condyloid, saddle, and ball-and-socket. | A: gomphoses. |
A catalyst can increase the rate of what, in general?
Here are the choices:
A. mechanicl reaction
B. consumption reaction
C. carbon reaction
D. chemical reaction | A catalyst is a substance that increases the rate of a chemical reaction. The presence of a catalyst is one of several factors that influence the rate of chemical reactions. (Other factors include the temperature, concentration, and surface area of reactants. ) A catalyst isn’t a reactant in the chemical reaction it speeds up. As a result, it isn’t changed or used up in the reaction, so it can go on to catalyze many more reactions. | D: chemical reaction. |
Which crust lies deep inside the ocean?
Here are the choices:
A. shallowest
B. youngest
C. thickest
D. oldest | The oldest crust is coldest and lies deepest in the ocean. | D: oldest. |
What is the most significant cause of respiratory disease as well as cardiovascular disease and cancer?
Here are the choices:
A. running
B. driving
C. smoking
D. sleeping | Smoking is the most significant cause of respiratory disease as well as cardiovascular disease and cancer. Exposure to tobacco smoke by smoking or by breathing air that contains tobacco smoke is the leading cause of preventable death in the United States. Regular smokers die about 10 years earlier than nonsmokers. The Centers for Disease Control and Prevention (CDC) describes tobacco use as "the single most important preventable risk to human health in developed countries and an important cause of [early] death worldwide. ". | C: smoking. |
What type of light can you feel as heat but not see and has the longest wavelengths and lowest frequencies?
Here are the choices:
A. ultraviolet light
B. thermal light
C. solar light
D. infrared light | Infrared light is light with the longest wavelengths and lowest frequencies. You can’t see infrared light, but you can feel it as heat. Besides the sun, flames and living things give off infrared light. | D: infrared light. |
Ionic, molecular, covalent, and metallic are major types of what state of matter?
Here are the choices:
A. gas
B. plasma
C. liquid
D. solids | Summary The major types of solids are ionic, molecular, covalent, and metallic. Ionic solids consist of positively and negatively charged ions held together by electrostatic forces; the strength of the bonding is reflected in the lattice energy. Ionic solids tend to have high melting points and are rather hard. Molecular solids are held together by relatively weak forces, such as dipole–dipole interactions, hydrogen bonds, and London dispersion forces. As a result, they tend to be rather soft and have low melting points, which depend on their molecular structure. Covalent solids consist of two- or three-dimensional networks of Saylor URL: http://www. saylor. org/books. | D: solids. |
What forces keep the moon orbiting the earth?
Here are the choices:
A. magnetic
B. polar
C. cosmic
D. gravitational | This photograph was taken by Apollo 8 crewmember Bill Anders on December 24, 1968, showing the Earth rising above the lunar surface. Gravitational forces keep the moon orbiting the Earth. | D: gravitational. |
Snow and ice may also undergo which process where there is intense sunlight, very cold temperatures, and dry winds?
Here are the choices:
A. sublimation
B. increasefixation
C. amplification
D. crystalline | Snow and ice may also undergo sublimation under certain conditions. This is most likely to happen where there is intense sunlight, very cold temperatures, and dry winds. These conditions are often found on mountain peaks. As snow sublimates, it gradually shrinks without any runoff of liquid water. At the URL below, you can watch a time-lapse video showing sublimation of snow on the highest mountain in the Andes. | A: sublimation. |
Electromagnets can be controlled by controlling what type of current?
Here are the choices:
A. negative
B. magnetic
C. positive
D. electric | Besides their strength, another pro of electromagnets is the ability to control them by controlling the electric current. Turning the current on or off turns the magnetic field on or off. The amount of current flowing through the coil can also be changed to control the strength of the electromagnet. | D: electric. |
The rate of evolution is influenced by the rate of changes to what?
Here are the choices:
A. the environment
B. the earth
C. dna
D. migration | The rate of evolution is influenced by how quickly the environment is changing. Long periods of gradual evolutionary change may be interrupted by short bursts of rapid change. | A: the environment. |
What do you call a device that produces a very focused beam of visible light of just one wavelength and color?
Here are the choices:
A. laser
B. light meter
C. optical diffuser
D. fusion relay | Did you ever see a cat chase after a laser light, like the one in Figure below ? A laser is a device that produces a very focused beam of visible light of just one wavelength and color. Waves of laser light are synchronized so the crests and troughs of the waves line up. The diagram in Figure below shows why a beam of laser light is so focused compared with ordinary light from a flashlight. | A: laser. |
Bubbles in bread dough are created by what gas produced during alcoholic fermentation?
Here are the choices:
A. yeast dioxide
B. carbon dioxide
C. combustion dioxide
D. acid dioxide | In alcoholic fermentation, glycolysis is followed by a step that produces alcohol and carbon dioxide. This step also forms additional molecules of ATP. It occurs in yeast, such as the yeast in bread. Carbon dioxide from alcoholic fermentation creates gas bubbles in bread dough. The bubbles leave little holes in the bread after it bakes. You can see them in the bread in Figure below . The holes make the bread light and fluffy. | B: carbon dioxide. |
What is the capacity to cause change?
Here are the choices:
A. temperature
B. energy
C. mass
D. gravity | B: energy. | |
Ocean currents transfer heat from the equator towards what locations?
Here are the choices:
A. poles
B. tropical zones
C. east and west
D. continents | Ocean currents transfer heat from the Equator toward the poles. This moderates Earth's temperature. | A: poles. |
In sexual reproduction, two of what unite to produce an offspring?
Here are the choices:
A. gametes
B. chromosomes
C. DNA strands
D. spores | In sexual reproduction, two gametes unite to produce an offspring. Which two gametes is a matter of chance. The union of gametes occurs randomly. | A: gametes. |
What are the ends of long bones called?
Here are the choices:
A. cartilage
B. marrow extension
C. appendage
D. epiphysis | Long bones ossify and get longer as they grow and develop. These bones grow from their ends, known as the epiphysis, and the presence of a growth plate, or epiphyseal line, signifies that the bone is still growing. | D: epiphysis. |
Convection is the transfer of thermal energy by particles moving through what?
Here are the choices:
A. tissue
B. Solid
C. Metal
D. fluid | Convection is the transfer of thermal energy by particles moving through a fluid. Particles transfer energy by moving from warmer to cooler areas. That’s how energy is transferred in the soup in Figure above . Particles of soup near the bottom of the pot get hot first. They have more energy so they spread out and become less dense. With lower density, these particles rise to the top of the pot (see Figure below ). By the time they reach the top of the pot they have cooled off. They have less energy to move apart, so they become denser. With greater density, the particles sink to the bottom of the pot, and the cycle repeats. This loop of moving particles is called a convection current . | D: fluid. |
What happens when waves reach the shore?
Here are the choices:
A. diffuse and recede
B. surge and drown
C. topple and break
D. repel and attract | Figure below shows what happens to waves near shore. As waves move into shallow water, they start to touch the bottom. The base of the waves drag and slow. Soon the waves slow down and pile up. They get steeper and unstable as the top moves faster than the base. When they reach the shore, the waves topple over and break. | C: topple and break. |
What is an involuntary muscle contraction that moves rapidly along an organ like a wave called?
Here are the choices:
A. peristalsis
B. ruptured nerve
C. esophagus
D. apoptosis | The organs of the GI tract are lined with mucous membranes that secrete digestive enzymes and absorb nutrients. The organs are also covered by layers of muscle that enable peristalsis. Peristalsis is an involuntary muscle contraction that moves rapidly along an organ like a wave (see Figure below ). You can watch an animation of peristalsis at this link: http://en. wikipedia. org/wiki/File:Peristalsis. gif . | A: peristalsis. |
What is the purpose of water molds in fresh water environments?
Here are the choices:
A. fish food
B. wave production
C. decomposition
D. oxygen production | C: decomposition. | |
What corrosive substances capable of dissolving many metals can cause contamination if spilled?
Here are the choices:
A. bases
B. acids
C. salts
D. ions | Acids can dissolve many metals; a spilled acid can lead to contamination. | B: acids. |
What is always conserved in chemical reactions?
Here are the choices:
A. energy
B. mass
C. bonds
D. force | A: All chemical equations must be balanced. This means that there must be the same number of each type of atom on both sides of the arrow. That’s because mass is always conserved in chemical reactions. Count the number of hydrogen and oxygen atoms on each side of the arrow. There are two hydrogen atoms in both reactants and products. There are two oxygen atoms in the reactants but only one in the product. Therefore, equation 1 is not balanced. | B: mass. |
A polyatomic ion is an ion composed of more than one what?
Here are the choices:
A. nucleus
B. neutron
C. pair bond
D. atom | A polyatomic ion is an ion composed of more than one atom. For example, the ammonium ion consists of one nitrogen atom and four hydrogen atoms. Together, they comprise a single ion with a 1+ charge and a formula of NH 4 + . The carbonate ion consists of one carbon atom and three oxygen atoms, and it carries an overall charge of 2−. The formula of the carbonate ion is CO 3 2- . The atoms of a polyatomic ion are tightly bonded together, so the entire ion behaves as a single unit. Figure below shows several models, and Table below lists many of the most common polyatomic ions. | D: atom. |
Mutualism is an interaction between individuals of two different species that has what effect on both of them?
Here are the choices:
A. harmful
B. abnormal
C. beneficial
D. neutral | They live mutualistically with other organisms. Mutualistic fungi live harmlessly with other living organisms. Recall that mutualism is an interaction between individuals of two different species, in which both individuals benefit. | C: beneficial. |
What are the structural and functional units of the nervous system, which transmit nerve impulses to other cells?
Here are the choices:
A. neurons
B. axions
C. electrons
D. ions | Neurons are the structural and functional units of the nervous system. They consist of a cell body, dendrites, and axon. Neurons transmit nerve impulses to other cells. Types of neurons include sensory neurons, motor neurons, and interneurons. | A: neurons. |
If hot water becomes trapped, pressure may build up. when the water breaks free, it creates what?
Here are the choices:
A. geyser
B. steam
C. glacier
D. groundwater | If hot water becomes trapped, pressure may build up. When the water breaks free, it creates a geyser. | A: geyser. |
What electrical force is responsible for fission?
Here are the choices:
A. velocity
B. momentum
C. friction
D. repulsion | The strong force predominates and can cause nuclei of complex atoms with many protons to be stable. The electric force of repulsion is responsible for fission, the breaking apart of nuclei, and therefore also for atom bombs and nuclear power. A form of fission where a helium nucleus is a product, is called alpha radiation. The actions of the weak force give rise to beta radiation. A change in nuclear energy can also give rise to gamma radiation , high energy electromagnetic waves. Particles that emit alpha radiation, beta radiation, and gamma radiation go through the process of radioactive decay, which causes the heating of the molten core of the earth, and has even played a role in the mutations in our evolutionary history. Fission and fusion, the latter occurring when light nuclei combine to form new elements, are accompanied by copious amounts of gamma radiation. These processes often produce radioactive nuclei; in nature these radioactive nuclei were forged in the explosive deaths of ancient stars. | D: repulsion. |
Which law states that a pair of alleles is separated, or segregated, during the formation of gametes?
Here are the choices:
A. separation anxiety
B. law of equals
C. law of segregation
D. de facto segregation | Mendel summarized his findings in two laws: the Law of Segregation and the Law of Independent Assortment. The Law of Segregation is based on his findings from his first set of experiments. Mendel stated that heritable factors are segregated during gamete formation. More precisely, this law states that a pair of alleles is separated, or segregated, during the formation of gametes. During meiosis, homologous chromosomes are randomly separated. Each resulting gamete has an equal probability or chance of receiving either of the two alleles. In other words, each gamete has only one allele for each gene. | C: law of segregation. |
Sounds or pictures can be encoded in pulses of what, which are then sent through an optical fiber?
Here are the choices:
A. quasars
B. microwaves
C. kinetic energy
D. laser light | Besides entertaining a cat, laser light has many other uses. One use is carrying communication signals in optical fibers. Sounds or pictures are encoded in pulses of laser light, which are then sent through an optical fiber. All of the light reflects off the inside of the fiber, so none of it escapes. As a result, the signal remains strong even over long distances. More than one signal can travel through an optical fiber at the same time, as you can see in the Figure below . Optical fibers are used to carry telephone, cable TV, and Internet signals. | D: laser light. |
What substance are physical objects are made of?
Here are the choices:
A. friction
B. gravity
C. energy
D. matter | To understand minerals, we must first understand matter. Matter is the substance that physical objects are made of. | D: matter. |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.