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Which theorem states that, if a population meets certain conditions, it will be in equilibrium? | hardy - zeiss theorem | hardy- jacksons theorem | hardy - henkel theorem | hardy-weinberg theorem | The Hardy-Weinberg theorem states that, if a population meets certain conditions, it will be in equilibrium. In an equilibrium population, allele and genotype frequencies do not change over time. The conditions that must be met are no mutation, no migration, very large population size, random mating, and no natural selection. |
What is greatest source of hazardous waste? | heat | study | water | industry | The greatest source of hazardous waste is industry. Agriculture is another major source. Even households produce a lot of hazardous waste. |
A circuit that consists of two loops is called a what? | complex circuit | diverse circuit | unnatural circuit | parallel circuit | A circuit that consists of two loops is called a parallel circuit. If one loop of a parallel circuit is interrupted, current can still flow through the other loop. |
Hyenas and cockroaches are examples of what decomposers that consume the soft tissues of dead animals? | predators | parasites | foragers | scavengers | Scavengers are decomposers that consume the soft tissues of dead animals. Examples of scavengers include hyenas and cockroaches. |
What helps to convert some molecules to forms that can be taken up by other organisms? | scavangers | eukaryotes | protists | prokaryotes | |
As hydrostatic pressure in the kidneys increases, what happens to the amount of water leaving the capillares? | it stays the same | it decreases | it evaporates | it increases | Hydrostatic pressure is especially important in governing the movement of water in the nephrons of the kidneys to ensure proper filtering of the blood to form urine. As hydrostatic pressure in the kidneys increases, the amount of water leaving the capillaries also increases, and more urine filtrate is formed. If hydrostatic pressure in the kidneys drops too low, as can happen in dehydration, the functions of the kidneys will be impaired, and less nitrogenous wastes will be removed from the bloodstream. Extreme dehydration can result in kidney failure. Fluid also moves between compartments along an osmotic gradient. Recall that an osmotic gradient is produced by the difference in concentration of all solutes on either side of a semi-permeable membrane. The magnitude of the osmotic gradient is proportional to the difference in the concentration of solutes on one side of the cell membrane to that on the other side. Water will move by osmosis from the side where its concentration is high (and the concentration of solute is low) to the side of the membrane where its concentration is low (and the concentration of solute is high). In the body, water moves by osmosis from plasma to the IF (and the reverse) and from the IF to the ICF (and the reverse). In the body, water moves constantly into and out of fluid compartments as conditions change in different parts of the body. For example, if you are sweating, you will lose water through your skin. Sweating depletes your tissues of water and increases the solute concentration in those tissues. As this happens, water diffuses from your blood into sweat glands and surrounding skin tissues that have become dehydrated because of the osmotic gradient. Additionally, as water leaves the blood, it is replaced by the water in other tissues throughout your body that are not dehydrated. If this continues, dehydration spreads throughout the body. When a dehydrated person drinks water and rehydrates, the water is redistributed by the same gradient, but in the opposite direction, replenishing water in all of the tissues. |
What is the percentage of production transferred from one trophic level to the next | hypothesized efficiency | robust efficiency | underlie efficiency | trophic efficiency | |
What is the metal part of the compound named as? | the basic | the base | the source | the element | The metal part of the compound is named as the element. |
How do plants and algae both make food? | Digestion. | atherosclerosis | spermatogenesis | photosynthesis | Like plants, algae contain chlorophyll and make food by photosynthesis. |
All dinosaurs (except those which led to birds) went extinct at the end of which period? | Paleogene | Tertiary | Jurassic | cretaceous | At the end of the Cretaceous Period, or 65 million years ago, all dinosaurs (except those which led to birds) went extinct. Some scientists believe a possible cause is a collision between the Earth and a comet or asteroid. The collision could have caused tidal waves, changed the climate, increased atmospheric dust and clouds, and reduced sunlight by 10-20%. A decrease in photosynthesis would have resulted in less plant food, leading to the extinction of the dinosaurs. |
What is destroying the layer of good ozone? | climate change | greenhouse gas | water pollution | air pollution | Unfortunately, the layer of good ozone is being destroyed by air pollution. The chief culprits are chlorine and bromine gases. They are released in aerosol sprays, coolants, and other products. Loss of ozone has created an ozone hole over Antarctica. Ozone depletion results in higher levels of UV radiation reaching Earth. In humans, this increases skin cancers and eye cataracts. It also disturbs the nitrogen cycle, kills plankton, and disrupts ocean food webs. The total loss of the ozone layer would be devastating to most life. It’s rate of loss has slowed with restrictions on pollutants, but it is still at risk. |
In which state does matter need to be for nuclear fusion? | gaseous state | cells state | solid state | plasma state | Unfortunately, using energy from nuclear fusion is far from a reality. Scientists are a long way from developing the necessary technology. One problem is raising temperatures high enough for fusion to take place. Another problem is that matter this hot exists only in the plasma state. There are no known materials that can contain plasma, although a magnet might be able to do it. That’s because plasma consists of ions and responds to magnetism. You can learn more about research on nuclear fusion at the URL below. |
Just as salty taste involves perception of sodium ions in saliva, what taste correlates with presence of glucose? | sour | salty | bitter | sweet | Salty taste is simply the perception of sodium ions (Na+) in the saliva. When you eat something salty, the salt crystals dissociate into the component ions Na+ and Cl–, which dissolve into the saliva in your mouth. The Na+ concentration becomes high outside the gustatory cells, creating a strong concentration gradient that drives the diffusion of the ion into the cells. The entry of Na+ into these cells results in the depolarization of the cell membrane and the generation of a receptor potential. Sour taste is the perception of H+ concentration. Just as with sodium ions in salty flavors, these hydrogen ions enter the cell and trigger depolarization. Sour flavors are, essentially, the perception of acids in our food. Increasing hydrogen ion concentrations in the saliva (lowering saliva pH) triggers progressively stronger graded potentials in the gustatory cells. For example, orange juice—which contains citric acid—will taste sour because it has a pH value of approximately 3. Of course, it is often sweetened so that the sour taste is masked. The first two tastes (salty and sour) are triggered by the cations Na+ and H+. The other tastes result from food molecules binding to a G protein–coupled receptor. A G protein signal transduction system ultimately leads to depolarization of the gustatory cell. The sweet taste is the sensitivity of gustatory cells to the presence of glucose dissolved in the saliva. Other monosaccharides such as fructose, or artificial sweeteners such as aspartame (NutraSweet™), saccharine, or sucralose (Splenda™) also activate the sweet receptors. The affinity for each of these molecules varies, and some will taste sweeter than glucose because they bind to the G protein–coupled receptor differently. Bitter taste is similar to sweet in that food molecules bind to G protein–coupled receptors. However, there are a number of different ways in which this can happen because there are a large diversity of bitter-tasting molecules. Some bitter molecules depolarize gustatory cells, whereas others hyperpolarize gustatory cells. Likewise, some bitter molecules increase G protein. |
How is eye color in humans determined? | temperature of the womb | random chance | by the father | multiple genes | Eye color in humans is determined by multiple genes. Use the Eye Color Calculator (http://openstaxcollege. org/l/ eye_color_calc) to predict the eye color of children from parental eye color. In some cases, several genes can contribute to aspects of a common phenotype without their gene products ever directly interacting. In the case of organ development, for instance, genes may be expressed sequentially, with each gene adding to the complexity and specificity of the organ. Genes may function in complementary or synergistic fashions, such that two or more genes need to be expressed simultaneously to affect a phenotype. Genes may also oppose each other, with one gene modifying the expression of another. In epistasis, the interaction between genes is antagonistic, such that one gene masks or interferes with the expression of another. “Epistasis” is a word composed of Greek roots that mean “standing upon. ” The alleles that are being masked or silenced are said to be hypostatic to the epistatic alleles that are doing the masking. Often the biochemical basis of epistasis is a gene pathway in which the expression of one gene is dependent on the function of a gene that precedes or follows it in the pathway. An example of epistasis is pigmentation in mice. The wild-type coat color, agouti (AA), is dominant to solid-colored fur (aa). However, a separate gene (C) is necessary for pigment production. A mouse with a recessive c allele at this locus is unable to produce pigment and is albino regardless of the allele present at locus A (Figure 12.20). Therefore, the genotypes AAcc, Aacc, and aacc all produce the same albino phenotype. A cross between heterozygotes for both genes (AaCc x AaCc) would generate offspring with a phenotypic ratio of 9 agouti:3 solid color:4 albino (Figure 12.20). In this case, the C gene is epistatic to the A gene. |
What term is given to flatworms because they lack a body cavity? | sporazoa | pores | sporozoans | acoelomates | Flatworms have no true body cavity, but they do have bilateral symmetry. Due to the lack of a body cavity,flatworms are known as acoelomates. |
Some soil water can flow through easily. what kind of soil is this? | dense | Stationary | porous | permeable | Water can flow easily through a permeable soil. Spaces between the inorganic particles are large and well connected. Sandy or silty soils are permeable, water-draining types of soils. |
What is contained in the cavity of a long bone's central shaft? | cells | blood | calcium | marrow | Long bones are longer than they are wide and have a shaft and two ends. The diaphysis, or central shaft, contains bone marrow in a marrow cavity. The rounded ends, the epiphyses, are covered with articular cartilage and are filled with red bone marrow, which produces blood cells (Figure 38.17). Most of the limb bones are long bones—for example, the femur, tibia, ulna, and radius. Exceptions to this include the patella and the bones of the wrist and ankle. |
Bacterial contamination of foods can lead to digestive problems called what? | butterflies in your stomach | cancer | the flu | food poisoning | Bacterial contamination of foods can lead to digestive problems, an illness known as food poisoning . Raw eggs and undercooked meats commonly carry the bacteria that can cause food poisoning. Food poisoning can be prevented by cooking meat thoroughly and washing surfaces that have been in contact with raw meat. Washing your hands before and after handling food also helps prevent contamination. |
What can be looked at to see a record of how horses evolved? | pattern records | erosion records | carbon dating | fossil records | Evolution of the Horse. The fossil record reveals how horses evolved. |
What natural destructive element cuts away at rock forming river valleys? | air | sediment | lava | water | Lactic acid fermentation converts the 3-carbon pyruvate to the 3-carbon lactic acid (C 3 H 6 O 3 ) (see Figure below ) and regenerates NAD + in the process, allowing glycolysis to continue to make ATP in low-oxygen conditions. Since there is a limited supply of NAD + available in any given cell, this electron acceptor must be regenerated to allow ATP production to continue. To achieve this, NADH donates its extra electrons to the pyruvate molecules, regenerating NAD + . Lactic acid is formed by the reduction of pyruvate. |
What do we call an interruption in the normal conduction pathway of the heart? | heartburn | heart attack | infarction | heart block | A heart block refers to an interruption in the normal conduction pathway. The nomenclature for these is very straightforward. SA nodal blocks occur within the SA node. AV nodal blocks occur within the AV node. Infra-Hisian blocks involve the bundle of His. Bundle branch blocks occur within either the left or right atrioventricular bundle branches. |
Mixtures that have the same composition throughout are known as what kinds of mixtures? | heterogeneous | contiguous | zygomatic | homogeneous | Some mixtures are homogeneous. This means they have the same composition throughout. An example is salt water in the ocean. Ocean water everywhere is about 3.5 percent salt. |
The wavelength of a what type of wave can be measured as the distance between two adjacent compressions? | vertical | horizontal | lateral | longitudinal | The wavelength of a transverse wave can be measured as the distance between two adjacent crests. The wavelength of a longitudinal wave can be measured as the distance between two adjacent compressions. |
What kind of muscle is found in the heart? | pulminary | cord | respiratory | cardiac | When most people think of muscles, they think of the muscles that are visible just under the skin, particularly of the limbs. These are skeletal muscles, so-named because most of them move the skeleton. But there are two other types of muscle in the body, with distinctly different jobs. Cardiac muscle, found in the heart, is concerned with pumping blood through the circulatory system. Smooth muscle is concerned with various involuntary movements, such as having one’s hair stand on end when cold or frightened, or moving food through the digestive system. This chapter will examine the structure and function of these three types of muscles. |
Streamlines are smooth and continuous when flow is laminar, but break up and mix when flow is what? | slow | atmospheric | volcanic | turbulent | Figure 12.11 shows schematically how laminar and turbulent flow differ. Layers flow without mixing when flow is laminar. When there is turbulence, the layers mix, and there are significant velocities in directions other than the overall direction of flow. The lines that are shown in many illustrations are the paths followed by small volumes of fluids. These are called streamlines. Streamlines are smooth and continuous when flow is laminar, but break up and mix when flow is turbulent. Turbulence has two main causes. First, any obstruction or sharp corner, such as in a faucet, creates turbulence by imparting velocities perpendicular to the flow. Second, high speeds cause turbulence. The drag both between adjacent layers of fluid and between the fluid and its surroundings forms swirls and eddies, if the speed is great enough. We shall concentrate on laminar flow for the remainder of this section, leaving certain aspects of turbulence for later sections. |
What does water treatment do to water? | adds flavor | increases volume | restores bacteria | removes unwanted substances | Water treatment is a series of processes that remove unwanted substances from water. More processes are needed to purify water for drinking than for other uses. |
What is named after the type of enzyme they interact with in the cell? | nitrogen proteins | oxygen proteins | function proteins | receptor proteins | In eukaryotic cells, most of the intracellular proteins that are activated by a ligand binding to a receptor protein are enzymes. Receptor proteins are named after the type of enzyme that they interact with inside the cell. These enzymes include G proteins and protein kinases, likewise there are G-protein-linked receptors and tyrosine kinase receptors. A kinase is a protein involved in phosphorylation. Tyrosine kinase receptors bind many polypeptide growth factors, cytokines, and hormones. Once the ligand is bound, these receptors specifically phosphorylate tyrosine amino acids, activating the signal transduction process inside the cell. |
What types of genes encode transcription factors? | rohail genes | glycosyl transferases | isozyme genes | homeobox genes | Homeobox genes are involved in the regulation of genes important to development. They encode transcription factors. |
What factor largely determines the distinguishing features of terrestrial biomes? | migration | density | sea level | climate | Terrestrial biomes include all the land areas on Earth where organisms live. The distinguishing features of terrestrial biomes are determined mainly by climate. Terrestrial biomes include tundras, temperate forests and grasslands, chaparral, temperate and tropical deserts, and tropical forests and grasslands. |
What is the term for vascular plants that reproduce with seeds? | strain plants | Reproductive Plants | mother plants | seed plants | Seed plants are vascular plants that reproduce with seeds. Modern seed plants are called spermatophytes. Seeds allow the plants to reproduce without water. Most vascular plants today are seed plants. |
What is thought to be the oldest eukaryotes? | arthropods | amoebas | prokaryotes | protists | Protists are eukaryotes in the Protist Kingdom. Most are single-celled organisms. Protists are thought to be the oldest eukaryotes. They probably evolved when some prokaryotic cells invaded or were engulfed by others. |
Which landmark book on evolution via natural selection did charles darwin publish in 1859? | on various kinds of animals | on the origin of mammals | on the ethnic of species | on the origin of species | Darwin finally published his theory of evolution by natural selection in 1859. He presented it in his book On the Origin of Species . The book is very detailed and includes a lot of evidence for the theory. Darwin’s book changed science forever. The theory of evolution by natural selection became the unifying theory of all life science. |
Archaeans help break down sewage in waste treatment plants, so they fulfill what important role? | pollenation | producers | consumers | decomposer | Like bacteria, archaeans are important decomposers. For example, archaeans help break down sewage in waste treatment plants. As decomposers, they help recycle carbon and nitrogen. |
If an atom gains electrons, it becomes what? | neutral | anion | a cation | an ion | If an atom gains electrons, it becomes an ion. Is the ion positively or negatively charged? Explain your answer. |
The formula mass of a covalent compound is also called the what? | nucleus mass | atomic mass | ionic mass | molecular mass | Summary 3.1 Formula Mass and the Mole Concept The formula mass of a substance is the sum of the average atomic masses of each atom represented in the chemical formula and is expressed in atomic mass units. The formula mass of a covalent compound is also called the molecular mass. A convenient amount unit for expressing very large numbers of atoms or molecules is the mole. Experimental measurements have determined the number of entities composing 1 mole of substance to be 6.022 × 1023, a quantity called Avogadro’s number. The mass in grams of 1 mole of substance is its molar mass. Due to the use of the same reference substance in defining the atomic mass unit and the mole, the formula mass (amu) and molar mass (g/mol) for any substance are numerically equivalent (for example, one H2O molecule weighs approximately18 amu and 1 mole of H2O molecules weighs approximately 18 g). 3.2 Determining Empirical and Molecular Formulas The chemical identity of a substance is defined by the types and relative numbers of atoms composing its fundamental entities (molecules in the case of covalent compounds, ions in the case of ionic compounds). A compound’s percent composition provides the mass percentage of each element in the compound, and it is often experimentally determined and used to derive the compound’s empirical formula. The empirical formula mass of a covalent compound may be compared to the compound’s molecular or molar mass to derive a molecular formula. 3.3 Molarity Solutions are homogeneous mixtures. Many solutions contain one component, called the solvent, in which other components, called solutes, are dissolved. An aqueous solution is one for which the solvent is water. The concentration of a solution is a measure of the relative amount of solute in a given amount of solution. Concentrations may be measured using various units, with one very useful unit being molarity, defined as the number of moles of solute per liter of solution. The solute concentration of a solution may be decreased by adding solvent, a process referred to as dilution. The dilution equation is a simple relation between concentrations and volumes of a solution before and after dilution. 3.4 Other Units for Solution Concentrations In addition to molarity, a number of other solution concentration units are used in various applications. Percentage concentrations based on the solution components’ masses, volumes, or both are useful for expressing relatively high concentrations, whereas lower concentrations are conveniently expressed using ppm or ppb units. These units are popular in environmental, medical, and other fields where mole-based units such as molarity are not as commonly used. |
Both pathways that isolate a population reproductively in some form, allopatric and sympatric describe what, which means the creation of new species? | bacterial | accumulation | extinction | speciation | 18.2 Formation of New Species Speciation occurs along two main pathways: geographic separation (allopatric speciation) and through mechanisms that occur within a shared habitat (sympatric speciation). Both pathways isolate a population reproductively in some form. Mechanisms of reproductive isolation act as barriers between closely related species, enabling them to diverge and exist as genetically independent species. Prezygotic barriers block reproduction prior to formation of a zygote, whereas postzygotic barriers block reproduction after fertilization occurs. For a new species to develop, something must cause a breach in the reproductive barriers. Sympatric speciation can occur through errors in meiosis that form gametes with extra chromosomes (polyploidy). Autopolyploidy occurs within a single species, whereas allopolyploidy occurs between closely related species. |
Common disease of what system include asthma, pneumonia, and emphysema? | the glandular system | the fecal system | the digestive system | the respiratory system | Common diseases of the respiratory system include asthma, pneumonia, and emphysema. All of them are diseases of the lungs. The main way to keep your respiratory system healthy is to avoid smoking or breathing in the smoke of others. |
Translucent matter is matter that transmits and does what else to light? | condenses | absorbs | reflects | scatters | Translucent matter is matter that transmits but scatters light. Light passes through a translucent object but you cannot see clearly through the object because the light is scattered in all directions. The frosted glass doors in the figure are translucent. |
Diet correlates with the length of what organ system in vertebrates? | circulatory | respiratory | reproductive | digestive | |
What is the process of processing used material into new ones called? | reuse | remake | renew | recycling | Now we move on to recycle. Sometimes it may be difficult to understand the differences between reusing and recycling. Recycling involves processing used materials in order to make them suitable for other uses. That usually means taking a used item, breaking it down, and reusing the pieces. Even though recycling requires extra energy, it does often make use of items which are broken, worn out, or cannot be reused. |
What equals the mass of the object (in kilograms) times the acceleration due to gravity (9.8 m/s 2 )? | velocity | speed of light | density | weight | Weight is a measure of the force of gravity pulling on an object of a given mass. It equals the mass of the object (in kilograms) times the acceleration due to gravity (9.8 m/s 2 ). |
Where does visible light fall in between on the electromagnetic spectrum? | radio and infrared | infrared light and specific light | infrared light and gamma ray | infrared light and ultraviolet light | The only light that people can see is called visible light . It refers to a very narrow range of wavelengths in the electromagnetic spectrum that falls between infrared light and ultraviolet light. Within the visible range, we see light of different wavelengths as different colors of light, from red light, which has the longest wavelength, to violet light, which has the shortest wavelength. You can see the spectrum of colors of visible light in Figure below . When all of the wavelengths are combined, as they are in sunlight, visible light appears white. You can learn more about visible light in the chapter "Visible Light" and at the URL below. |
Having polar bonds may make a covalent compound what? | neutral | ionic | negatively charged | polar | Having polar bonds may make a covalent compound polar. A polar compound is one in which there is a slight difference in charge between opposite ends of the molecule. All polar compounds contain polar bonds. But having polar bonds does not necessarily result in a polar compound. It depends on how the atoms are arranged. This is illustrated in Figure below . Both molecules in the figure contain polar bonds, but only formaldehyde is a polar compound. Why is carbon dioxide nonpolar?. |
Shortening of muscle fibers is called what?` | shrinking | diffusion | diffusion | contraction | Each muscle in the body is made up of cells called muscle fibers. Muscle fibers are long, thin cells that can do something that other cells cannot do—they are able to get shorter. Shortening of muscle fibers is called contraction . Muscle fibers can contract because they are made of proteins, called actin and myosin, that form long filaments (or fibers). When muscles contract, these protein filaments slide or glide past one another, shortening the length of the cell. When your muscles relax, the length extends back to the previous position. Nearly all movement in the body is the result of muscle contraction. |
About how many thunderstorms are there each year worldwide? | 23 million | 21 million | 17 million | 14 million | Thunderstorms are are known for their heavy rains and lightning. In strong thunderstorms, hail and high winds are also likely. Thunderstorms are very common. Worldwide, there are about 14 million of them each year! In the U. S. , they are most common — and strongest — in the Midwest. |
What are a group of protists whose monophyly is well supported by molecular systematics? | mycetozoa | euglenozoa | sporozoans | alveolates | |
What is measured by the intensity of the sound waves? | pitch | inputs | tone | loudness | Loudness refers to how loud or soft a sound seems to a listener. The loudness of sound is determined, in turn, by the intensity of the sound waves. Intensity is a measure of the amount of energy in sound waves. The unit of intensity is the decibel (dB) . |
Parasitic fungi often cause illness and may eventually do what to their hosts? | become them | reproduce with them | mutate them | kill them | Parasitic fungi often cause illness and may eventually kill their host. They are the major cause of disease in agricultural plants. Fungi also parasitize animals, such as the insect pictured in Figure below . Fungi even parasitize humans. Did you ever have athelete’s foot? If so, you were the host of a parasitic fungus. |
Coronary heart disease is caused when what blocks coronary arteries? | fats | proteins | carbohydrates | plaque | If plaque blocks coronary arteries that supply blood to the heart, coronary heart disease results. Poor blood flow to the heart may cause chest pain or a heart attack. A heart attack occurs when the blood supply to part of the heart muscle is completely blocked so that cardiac muscle cells die. Coronary heart disease is the leading cause of death in U. S adults. |
Air is an example of what state of matter? | plasma | solid | liquid | gas | Because air is a gas, its molecules have a lot of energy. Air molecules move a lot and bump into things. For this reason, they exert pressure. Air pressure is defined as the weight of the air pressing against a given area. |
What descend from clouds in funnel-like shapes that spin violently, producing powerful winds? | hurricanes | currents | rains | tornadoes | Figure 10.1 The mention of a tornado conjures up images of raw destructive power. Tornadoes blow houses away as if they were made of paper and have been known to pierce tree trunks with pieces of straw. They descend from clouds in funnel-like shapes that spin violently, particularly at the bottom where they are most narrow, producing winds as high as 500 km/h. (credit: Daphne Zaras, U. National Oceanic and Atmospheric Administration). |
What term describes the long-term, predictable atmospheric conditions of a specific area? | solar activity | hemosphere | wind patterns | climate | Climate and Weather A common misconception about global climate change is that a specific weather event occurring in a particular region (for example, a very cool week in June in central Indiana) is evidence of global climate change. However, a cold week in June is a weather-related event and not a climate-related one. These misconceptions often arise because of confusion over the terms climate and weather. Climate refers to the long-term, predictable atmospheric conditions of a specific area. The climate of a biome is characterized by having consistent temperature and annual rainfall ranges. Climate does not address the amount of rain that fell on one particular day in a biome or the colder-than-average temperatures that occurred on one day. In contrast, weather refers to the conditions of the atmosphere during a short period of time. Weather forecasts are usually made for 48-hour cycles. Long-range weather forecasts are available but can be unreliable. To better understand the difference between climate and weather, imagine that you are planning an outdoor event in northern Wisconsin. You would be thinking about climate when you plan the event in the summer rather than the winter because you have long-term knowledge that any given Saturday in the months of May to August would be a better choice for an outdoor event in Wisconsin than any given Saturday in January. However, you cannot determine the specific day that the event should be held on because it is difficult to accurately predict the weather on a specific day. Climate can be considered “average” weather. |
Between meals, when the level of blood glucose drops below a certain point, a signal is sent to what organ saying “make more glucose"? | brain | pancreas | kidney | liver | Shortly after eating, there is a surplus of glucose in the body. Some of it will be used immediately, but the rest is stored in the form of glycogen. Between meals, when the level of glucose in the blood drops below a certain point, a signal is sent to the liver that says “make more glucose. ” In response, the glycogen in the liver is broken down and the resulting glucose is released into the bloodstream. |
Where does the krebs cycle take place? | in the beam | in the nitrogen | in the ozone | in the matrix | The Krebs cycle and electron transport occur in the mitochondria. The Krebs cycle takes place in the matrix, and electron transport takes place on the inner membrane. |
What state of matter is like a liquid in that particles are in contact with each other, but unlike liquids in that the intermolecular forces are strong enough to hold the particles in place? | fluids | plasmas | gases | solids | A solid is like a liquid in that particles are in contact with each other. Solids are unlike liquids in that the intermolecular forces are strong enough to hold the particles in place. At low enough temperatures, all substances are solids (helium is the lone exception), but the temperature at which the solid state becomes the stable phase varies widely among substances, from 20 K (−253°C) for hydrogen to over 3,900 K (3,600°C) for carbon. The solid phase has several characteristics. First, solids maintain their shape. They do not fill their entire containers like gases do, and they do not adopt the shape of their containers like liquids do. They cannot be easily compressed like gases can, and they have relatively high densities. Solids may also demonstrate a variety of properties. For example, many metals can be beaten into thin sheets or drawn into wires, while compounds such as NaCl will shatter if they are struck. Some metals, such as sodium and potassium, are rather soft, while others, such as diamond, are very hard and can easily scratch other substances. Appearances differ as well: most metals are shiny and silvery, but sulfur (a nonmetal) is yellow, and ionic compounds can take on a rainbow of colors. Solid metals conduct electricity and heat, while ionic solids do not. Many solids are opaque, but some are transparent. Some dissolve in water, but some do not. Figure 10.13 "Properties of Solids" shows two solids that exemplify the similar and dissimilar properties of solids. Figure 10.13 Properties of Solids. |
What is the term for a natural situation which arises to physically divide organisms? | extinction | assimilation | reproduction | vicariance | If the two isolated populations are brought back together and the hybrid offspring that formed from matings between individuals of the two populations have lower survivorship or reduced fertility, then selection will favor individuals that are able to discriminate between potential mates of their own population and the other population. This selection will enhance the reproductive isolation. Isolation of populations leading to allopatric speciation can occur in a variety of ways: from a river forming a new branch, erosion forming a new valley, or a group of organisms traveling to a new location without the ability to return, such as seeds floating over the ocean to an island. The nature of the geographic separation necessary to isolate populations depends entirely on the biology of the organism and its potential for dispersal. If two flying insect populations took up residence in separate nearby valleys, chances are that individuals from each population would fly back and forth, continuing gene flow. However, if two rodent populations became divided by the formation of a new lake, continued gene flow would be unlikely; therefore, speciation would be more likely. Biologists group allopatric processes into two categories. If a few members of a species move to a new geographical area, this is called dispersal. If a natural situation arises to physically divide organisms, this is called vicariance. Scientists have documented numerous cases of allopatric speciation taking place. For example, along the west coast of the United States, two separate subspecies of spotted owls exist. The northern spotted owl has genetic and phenotypic differences from its close relative, the Mexican spotted owl, which lives in the south (Figure 11.15). The cause of their initial separation is not clear, but it may have been caused by the glaciers of the ice age dividing an initial population into [5] two. |
Digestion of carbohydrates is performed by several enzymes. starch and glycogen are broken down into glucose by amylase and maltase. sucrose (table sugar) and lactose (milk sugar) are broken down by sucrase and this? | hydrolase | lipase | pepsin | lactase | Figure 34.16 Digestion of carbohydrates is performed by several enzymes. Starch and glycogen are broken down into glucose by amylase and maltase. Sucrose (table sugar) and lactose (milk sugar) are broken down by sucrase and lactase, respectively. |
What is defined as a phasic change in muscle tone? | susceptibility | elasticity | gastrointestinal | spasticity | Muscle Tone Skeletal muscles are rarely completely relaxed, or flaccid. Even if a muscle is not producing movement, it is contracted a small amount to maintain its contractile proteins and produce muscle tone. The tension produced by muscle tone allows muscles to continually stabilize joints and maintain posture. Muscle tone is accomplished by a complex interaction between the nervous system and skeletal muscles that results in the activation of a few motor units at a time, most likely in a cyclical manner. In this manner, muscles never fatigue completely, as some motor units can recover while others are active. The absence of the low-level contractions that lead to muscle tone is referred to as hypotonia or atrophy, and can result from damage to parts of the central nervous system (CNS), such as the cerebellum, or from loss of innervations to a skeletal muscle, as in poliomyelitis. Hypotonic muscles have a flaccid appearance and display functional impairments, such as weak reflexes. Conversely, excessive muscle tone is referred to as hypertonia, accompanied by hyperreflexia (excessive reflex responses), often the result of damage to upper motor neurons in the CNS. Hypertonia can present with muscle rigidity (as seen in Parkinson’s disease) or spasticity, a phasic change in muscle tone, where a limb will “snap” back from passive stretching (as seen in some strokes). |
What is a force that opposes motion between any surfaces that are touching? | gravity | vibration | tension | friction | Friction is a force that opposes motion between any surfaces that are touching. |
What are structures that have a common function and suggest common ancestry? | monogamous structures | reversible structures | analogous structures | homologous structures | Homologous structures are structures that have a common function and suggest common ancestry. For example, homologous structures include the limbs of mammals, such as bats, lions, whales, and humans, which all have a common ancestor. Different mammals may use their limbs for walking, running, swimming or flying. The method the mammal uses to move is considered a common function. |
Which type of cell division halves the number of chromosomes? | mitosis | fragmentation | budding | meiosis | Meiosis is a type of cell division that halves the number of chromosomes. |
Objects in motion that return to the same position after a fixed period of time are said to be in what? | homeostasis | resonant motion | kinetic motion | harmonic motion | Objects in motion that return to the same position after a fixed period of time are said to be in harmonic motion. Objects in harmonic motion have the ability to transfer some of their energy over large distances. They do so by creating waves in a medium. Imagine pushing up and down on the surface of a bathtub filled with water. Water acts as the medium that carries energy from your hand to the edges of the bathtub. Waves transfer energy over a distance without direct contact with the initial source. Since waves are disturbances in an existing medium, they are considered phenomena and not actual objects. |
What is the relationship of multiple action potentials from a single cell resulting in a significant change in the membrane potential? | distinct summation | nature summation | bipolar summation | temporal summation | membrane is a positive 15 mV, meaning that the membrane depolarizes from -70 mV to -55 mV, then the graded potentials will result in the membrane reaching threshold. For receptor potentials, threshold is not a factor because the change in membrane potential for receptor cells directly causes neurotransmitter release. However, generator potentials can initiate action potentials in the sensory neuron axon, and postsynaptic potentials can initiate an action potential in the axon of other neurons. Graded potentials summate at a specific location at the beginning of the axon to initiate the action potential, namely the initial segment. For sensory neurons, which do not have a cell body between the dendrites and the axon, the initial segment is directly adjacent to the dendritic endings. For all other neurons, the axon hillock is essentially the initial segment of the axon, and it is where summation takes place. These locations have a high density of voltage-gated Na+ channels that initiate the depolarizing phase of the action potential. Summation can be spatial or temporal, meaning it can be the result of multiple graded potentials at different locations on the neuron, or all at the same place but separated in time. Spatial summation is related to associating the activity of multiple inputs to a neuron with each other. Temporal summation is the relationship of multiple action potentials from a single cell resulting in a significant change in the membrane potential. Spatial and temporal summation can act together, as well. |
Plant cells have cell walls that are made of what? | tissue | carbonate | nucleus | cellulose | Plants are multicellular eukaryotes that are placed in the Plant Kingdom . Plant cells have cell walls that are made of cellulose. Plant cells also have chloroplasts. They allow plants to make food by photosynthesis. In addition, plants have specialized reproductive organs that produce gametes. Male reproductive organs produce sperm. Female reproductive organs produce eggs. Male and female reproductive organs may be on the same plant or on different plants. |
What disease associated with smoking involves breakdown of walls of the alveoli, resulting in less gas exchange by the lungs? | pneumonia | leukemia | cancer | emphysema | Emphysema is a disease in which the walls of the alveoli break down so less gas can be exchanged by the lungs. The main symptom of emphysema is shortness of breath. The damage to the alveoli is usually caused by smoking and is permanent. |
Molds and yeasts are organisms in what kingdom? | aquatic | tissues | insects | fungus | Fungi are eukaryotes in the Fungus Kingdom. Fungi include molds, which are multicellular, and yeasts, which are single-celled. |
Bacteria can be used to make cheese from milk. the bacteria turn the milk sugars into what? | hydrochloric acid | acetic acid | ionic acid | lactic acid | Bacteria can be used to make cheese from milk. The bacteria turn the milk sugars into lactic acid. The acid is what causes the milk to curdle to form cheese. Bacteria are also involved in producing other foods. Yogurt is made by using bacteria to ferment milk ( Figure below ). Fermenting cabbage with bacteria produces sauerkraut. |
Independent assortment occurs when what go to opposite poles of the cell in anaphase i? | prokaryotes | receptors | ballasts | chromosomes | Independent assortment occurs when chromosomes go to opposite poles of the cell in anaphase I. Which chromosomes end up together at each pole is a matter of chance. You can see this in Figures 5.15 and 5.16 as well. |
What term is used to describe an immunity that occurs after exposure to an antigen either from a pathogen or a vaccination? | herd immunity | variation immunity | autoimmunity | adaptive immunity | The adaptive, or acquired, immune response takes days or even weeks to become established—much longer than the innate response; however, adaptive immunity is more specific to an invading pathogen. Adaptive immunity is an immunity that occurs after exposure to an antigen either from a pathogen or a vaccination. An antigen is a molecule that stimulates a response in the immune system. This part of the immune system is activated when the innate immune response is insufficient to control an infection. In fact, without information from the innate immune system, the adaptive response could not be mobilized. There are two types of adaptive responses: the cell-mediated immune response, which is controlled by activated T cells, and the humoral immune response, which is controlled by activated B cells and antibodies. Activated T and B cells whose surface binding sites are specific to the molecules on the pathogen greatly increase in numbers and attack the invading pathogen. Their attack can kill pathogens directly or they can secrete antibodies that enhance the phagocytosis of pathogens and disrupt the infection. Adaptive immunity also involves a memory to give the host long-term protection from reinfection with the same type of pathogen; on reexposure, this host memory will facilitate a rapid and powerful response. |
Changes in temperature, ph, and exposure to chemicals may lead to permanent changes in the shape of a protein, leading to loss of function known as what? | bioturbation | digestion | fermentation | denaturation | Proteins have different shapes and molecular weights; some proteins are globular in shape whereas others are fibrous in nature. For example, hemoglobin is a globular protein, but collagen, found in our skin, is a fibrous protein. Protein shape is critical to its function, and this shape is maintained by many different types of chemical bonds. Changes in temperature, pH, and exposure to chemicals may lead to permanent changes in the shape of the protein, leading to loss of function, known as denaturation. All proteins are made up of different arrangements of the same 20 types of amino acids. |
What term is used to describe phages capable of using both modes of replicating within a bacterium? | lambda phage | moderate phages | bacteriophage | temperate phages | |
Many observatories are built on high mountains to avoid interference from what? | animal life | airplanes | artificial light | the atmosphere | Telescopes on Earth all have one big problem: incoming light must pass through the atmosphere. This blocks some wavelengths of radiation. Also, motion in the atmosphere distorts light. You see this when you see stars twinkling in the night sky. Many observatories are built on high mountains. There is less air above the telescope, so there is less interference from the atmosphere. Space telescopes avoid problems from the atmosphere completely since they orbit outside the atmosphere. |
Like earth, the moon has a distinct crust, mantle, and what else? | atmosphere | temperature | polarity | core | Like Earth, the Moon has a distinct crust, mantle, and core. The crust is composed of igneous rock. This rock is rich in the elements oxygen, silicon, magnesium, and aluminum. On the near side, the Moon’s crust is about 60 kilometers thick. On the far side, the crust is about 100 kilometers thick. The mantle is made of rock like Earth’s mantle. The Moon has a small metallic core, perhaps 600 to 800 kilometers in diameter. The composition of the core is probably mostly iron with some sulfur and nickel. We learned this both from the rock samples gathered by astronauts and from spacecraft sent to the Moon. |
Reflection, refraction, and diffraction are examples of what type of interaction? | Currents | winds | Oscillations | waves | Waves interact with matter in several ways. The interactions occur when waves pass from one medium to another. The types of interactions are reflection, refraction, and diffraction. Each type of interaction is described in detail below. You can see animations of the three types at this URL: http://www. acoustics. salford. ac. uk/schools/teacher/lesson3/flash/whiteboardcomplete. swf . |
What type of molecules are found in the hydration shell of a dissolved ion? | oxygen | iron | carbon | water | |
Tuataras, lizards, and snakes are members of what subclass of reptiles? | staurikosaurus | dinosaurs | arthropods | lepidosaurs | |
What do waves deposit in relatively quiet areas along a shore? | snow | fish | mud | sand | Echo sounders were used to search for enemy submarines during World War II. The depths they recorded allowed scientists to piece together bathymetric maps of the seafloor. Multi-beam sounders work on research vessels today. |
What is the smallest unit of structure and function of all living organisms? | proton | atom | particle | cell | The cell is the smallest unit of structure and function of all living organisms. But this smallest of units still performs some very complex processes. In fact, for some organisms, just one cell must do everything necessary for life. |
What kind of fertilization do birds have? | sensitive fertilization | deep fertilization | asexual | internal fertilization | Birds reproduce sexually and have internal fertilization. Mating is generally preceded by courtship. Their amniotic eggs have hard shells and are laid in a nest. The eggs are usually incubated until they hatch. Most species have a relatively long period of parental care. |
What is the term for an organism, or single living thing? | unique | single-celled organism | loner | individual | An individual is an organism, or single living thing. |
Which of newton's laws states that the quantity of angular momentum in a closed system is fixed? | second conservation law | fourth conservation law | sixth conservation law | third conservation law | The third conservation law is conservation of angular momentum. This vector quantity is the product of rotational velocity and rotational inertia. In any closed system (including the universe) the quantity of angular momentum is fixed. Angular momentum can be transferred from one body to another, but cannot be lost or gained. If a system has its angular momentum changed from the outside it is caused by a torque. Torque is a force applied at a distance from the center of rotation. |
What is the force that slows down or stops motion? | thrust | resistance | tension | friction | |
What is it called when poles are in opposite positions? | demagnetization | reversed bonding | polar effect | reversed polarity | Looking at the magnetism of the seafloor, scientists discovered something astonishing. Many times in Earth’s history, the magnetic poles have switched positions. North becomes south, and south becomes north! When the north and south poles are aligned as they are now, geologists say it is normal polarity . When they are in the opposite position, they say that it is reversed polarity . |
What is a feature that prokaryotes lack? | plasma | epidermis | cell wall | nucleus | No doubt you've had a sore throat before, and you've probably eaten cheese or yogurt. If so, then you've already encountered the amazing world of prokaryotes. Prokaryotes are single-celled organisms that lack a nucleus. They also lack other membrane-bound organelles. Prokaryotes are tiny. They can only be viewed with a microscope (see Figure below ). But they are the most numerous organisms on Earth. Without them, the world would be a very different place. |
They had demonstrated that particles smaller than bacteria cause what? | damage | blood | flight | disease | Viruses are so small that they can be seen only with an electron microscope. Before electron microscopes were invented, scientists knew viruses must exist. How did they know? They had demonstrated that particles smaller than bacteria cause disease. |
The wrist and base of the hand are formed by what series of small bones arranged in distal and proximal rows? | cranial | ribs | patella | carpal | Carpal Bones The wrist and base of the hand are formed by a series of eight small carpal bones (see Figure 8.7). The carpal bones are arranged in two rows, forming a proximal row of four carpal bones and a distal row of four carpal bones. The bones in the proximal row, running from the lateral (thumb) side to the medial side, are the scaphoid (“boat-shaped”), lunate (“moonshaped”), triquetrum (“three-cornered”), and pisiform (“pea-shaped”) bones. The small, rounded pisiform bone articulates with the anterior surface of the triquetrum bone. The pisiform thus projects anteriorly, where it forms the bony bump that can be felt at the medial base of your hand. The distal bones (lateral to medial) are the trapezium (“table”), trapezoid (“resembles a table”), capitate (“head-shaped”), and hamate (“hooked bone”) bones. The hamate bone is characterized by a prominent bony extension on its anterior side called the hook of the hamate bone. A helpful mnemonic for remembering the arrangement of the carpal bones is “So Long To Pinky, Here Comes The Thumb. ” This mnemonic starts on the lateral side and names the proximal bones from lateral to medial (scaphoid, lunate, triquetrum, pisiform), then makes a U-turn to name the distal bones from medial to lateral (hamate, capitate, trapezoid, trapezium). Thus, it starts and finishes on the lateral side. |
What does an underwater spider use to breathe and keep alive? | metallic air bubble | forehead air bubble | gills | shiny air bubble | 11.8 Cohesion and Adhesion in Liquids: Surface Tension and Capillary Action Cohesion and Adhesion in Liquids Children blow soap bubbles and play in the spray of a sprinkler on a hot summer day. (See Figure 11.27. ) An underwater spider keeps his air supply in a shiny bubble he carries wrapped around him. A technician draws blood into a small-diameter tube just by touching it to a drop on a pricked finger. A premature infant struggles to inflate her lungs. What is the common thread? All these activities are dominated by the attractive forces between atoms and molecules in liquids—both within a liquid and between the liquid and its surroundings. Attractive forces between molecules of the same type are called cohesive forces. Liquids can, for example, be held in open containers because cohesive forces hold the molecules together. Attractive forces between molecules of different types are called adhesive forces. Such forces cause liquid drops to cling to window panes, for example. In this section we examine effects directly attributable to cohesive and adhesive forces in liquids. |
Amphibians are ectothermic vertebrates that divide their time between freshwater and what else? | arboreal habitats | saltwater | deserts | terrestrial habitats | Amphibians are ectothermic vertebrates that divide their time between freshwater and terrestrial habitats. They are the first true tetrapods, or vertebrates with four limbs. Amphibians breathe with gills as larvae and with lungs as adults. They have a three-chambered heart and relatively complex nervous system. |
Water plus other substances makes what? | element | oil | mixture | solution | Most water on Earth, like the water in the oceans, contains elements. The elements are mixed evenly through the water. Water plus other substances makes a solution. The particles are so small that they will not come out when you filter the water. But the elements in water can form solid mineral deposits. |
What type of polarization does a negative object create> | negative polarization | common polarization | simple polarization | opposite polarization | Figure 18.15 Both positive and negative objects attract a neutral object by polarizing its molecules. (a) A positive object brought near a neutral insulator polarizes its molecules. There is a slight shift in the distribution of the electrons orbiting the molecule, with unlike charges being brought nearer and like charges moved away. Since the electrostatic force decreases with distance, there is a net attraction. (b) A negative object produces the opposite polarization, but again attracts the neutral object. (c) The same effect occurs for a conductor; since the unlike charges are closer, there is a net attraction. |
What type of particles can a beta particle be? | anode or positron | diode or positron | cytoplasm or positron | electron or positron | |
The heme parts of a hemoglobin molecule bind with what element? | nitrogen | hydrogen | carbon | oxygen | Hemoglobin is an example of a transport protein in the blood. You can see how it works in Figure below . The heme parts of a hemoglobin molecule bind with oxygen. Each red blood cell has hundreds of hemoglobin molecules. This is how oxygen is carried in the blood to cells throughout the body. |
What is the term for flowering seed plants? | gymnosperms | spores | perennials | angiosperms | Angiosperms , or flowering seed plants, form seeds in ovaries. As the seeds develop, the ovaries may develop into fruits. Flowers attract pollinators, and fruits encourage animals to disperse the seeds. |
Do nonvascular or vascular plants have a dominant sporophyte generation? | perennial | nonvascular | deciduous | vascular | Unlike nonvascular plants, all vascular plants—including seedless vascular plants—have a dominant sporophyte generation. Seedless vascular plants include clubmosses and ferns. Figure below shows a typical fern life cycle. |
In mismatch repair, other enzymes remove and replace incorrectly paired nucleotides that have resulted from what? | evolution errors | typing errors | interaction errors | replication errors | |
What two structures are found on mars? | Trees and Canyons | geysers and canyons | Mountains and Creeks | volcanoes and canyons | The surface of Mars has volcanoes and canyons. There is a polar ice cap and channels that were once filled with water. Curiosity has found evidence of a flowing stream. |
What substances dissociate into ions when dissolved in water? | solvent | isotopes | magnetic | ionic | Ionic substances dissociate into ions when they dissolve in water, but most molecular substances do not. |
Organisms that depend on other organisms for food play what role in the food chain? | plant | fungus | producer | consumer | Consumers are organisms that depend on other organisms for food. They take in organic molecules by essentially “eating” other living things. They include all animals and fungi. (Fungi don't really “eat”; they absorb nutrients from other organisms. ) They also include many bacteria and even a few plants, such as the pitcher plant shown in Figure below . Consumers are also called heterotrophs. Heterotrophs are classified by what they eat:. |
What is the growing root tip protected by? | root hinge | root flap | tip cap | root cap | 30.3 Roots Roots help to anchor a plant, absorb water and minerals, and serve as storage sites for food. Taproots and fibrous roots are the two main types of root systems. In a taproot system, a main root grows vertically downward with a few lateral roots. Fibrous root systems arise at the base of the stem, where a cluster of roots forms a dense network that is shallower than a taproot. The growing root tip is protected by a root cap. The root tip has three main zones: a zone of cell division (cells are actively dividing), a zone of elongation (cells increase in length), and a zone of maturation (cells differentiate to form different kinds of cells). Root vascular tissue conducts water, minerals, and sugars. In some habitats, the roots of certain plants may be modified to form aerial roots or epiphytic roots. |
Ocean water appears cyan because microbes in the water preferentially absorb what color of light? | yellow | blue | green | red | Ocean water appears cyan because the microbes in the water preferentially absorb red light. What color does a red lobster appear on the ocean floor? How about a white shirt with blue stripes?. |