|
Genetic drift is a process based on _____. |
c. the role of chance |
|
Every few years a giant axe chops off the head of every person who is over 6 feet tall. How will this affect the human population? |
b. Alleles that promote "tallness" will decrease in frequency. |
|
Modern travel along with migration reduces the probability of _____ having an effect on the evolution of humans. |
d. genetic drift |
|
Crossing over, resulting in an increase in genetic variation, occurs between _____. a. nonsister chromatids of |
e. nonsister chromatids of homologous chromosomes |
|
What is true of microevolution? |
a. It is the kind of evolution that can change the relative abundance of a particular allele in a gene pool over the course of generations. |
|
The original source of all genetic variation is _____. |
a. mutation |
|
How does diploidy help to preserve genetic variation? |
a. It allows recessive alleles that may not be favored in the current environment to be preserved in the gene pool by propagation in heterozygotes. |
|
According to the Hardy-Weinberg theorem, the frequencies of alleles in a population will remain constant if _____ is the only process that affects the gene pool. |
e. sexual reproduction |
|
The evolutionary effects of genetic drift are greatest when _____. |
e. the population size is small |
|
What situation most likely explains the occasional high frequency of certain inherited disorders among human populations established by a small population? |
e. founder effect |
|
In evolutionary terms, an organism’s fitness is measured by its _____. |
e. contribution to the gene pool of the next generation |
|
What is the only evolutionary mechanism that consistently leads to adaptive evolution? |
a. natural selection |
|
Natural selection changes allele frequencies because some _______ survive and reproduce more successfully than others. |
d. individual |
|
No two people are genetically identical, except for identical twins. The main source of genetic variation among human individuals is: |
e. the reshuffling of alleles in sexual reproduction |
|
A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the gametes produced in the population contain the A1 allele. If the population is in Hardy-Weinberg equilibrium, what proportion of the flies carry both A1 and A2? |
c. 0.42 |
|
The fruit fly Drosophila melanogaster has an allele that confers resistance to DDT and similar insecticides. Laboratory strains of D. melanogaster have been established from flies collected in the wild in the 1930s (before the widespread use of insecticides) and the 1960s (after 20 years of DDT use). Lab strains established in the 1930s have no alleles for DDT resistance. In lab strains established in the 1960s, the frequency of the DDT-resistance allele is 37%. Which statement is correct? |
b. The evolutionary fitness associated with the heritable trait of DDT resistance changed once DDT use became widespread. |
|
One out of 10,000 babies born in North America is affected by cystic fibrosis, a recessive condition. Assuming that the North American human population is in Hardy-Weinberg equilibrium for this trait, what percentage of the population is heterozygous for this trait? (Remember the equation for a population in Hardy-Weinberg equilibrium: p2 + 2pq + q2 = 1.) |
a. 2% |
|
Allele frequencies in a gene pool may shift randomly and by chance. What is this random shift called? |
a. genetic drift |
|
Which statement correctly describes the role of chance in evolution? |
b. The ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism’s DNA. |
|
If the nucleotide variability of a locus equals 0%, what is the gene variability and number of alleles at that locus? |
c. gene variability = 0%; number of alleles = 1 |
|
There are 40 individuals in population 1, all with genotype A1A1, and there are 25 individuals in population 2, all with genotype A2A2. Assume that these populations are located far from each other and that their environmental conditions are very similar. Based on the information given here, the observed genetic variation is most likely an example of |
d. genetic drift |
|
What is the most important factor that holds a gene pool of a species together and prevents speciation? |
e. gene flow |
|
Two animals are considered members of different species if they _____. |
a. cannot mate and produce viable, fertile offspring |
|
Which of these is an example of temporal isolation? |
b. One species is nocturnal, and the other species is not. |
|
Which of the following is the first step in allopatric speciation? |
c. geographic isolation |
|
Use the following information to answer the question(s) below. Two populations of birds with somewhat different coloration live on opposite sides of a peninsula. The habitat between the populations is not suitable for these birds. When birds from the two populations are brought together, they produce young whose appearance is intermediate between the two parents. These offspring will breed with each other or with birds from either parent population, and all offspring of these pairings appear intermediate to various degrees.
The two populations are _____. |
b. not different species, under the biological species concept |
|
The common edible frog of Europe is a hybrid between two species, Rana lessonae and Rana ridibunda. The hybrids were first described in 1758 and have a wide distribution, from France across central Europe to Russia. Both male and female hybrids exist, but when they mate among themselves, they are rarely successful in producing offspring. What can you infer from this information? |
c. Postzygotic isolation exists between the two frog species. |
|
The approach to estimating phylogenetic trees is most like the approach of which species concept? |
b. phylogenetic species concept |
|
How are two different species most likely to evolve from one ancestral species? |
b. allopatrically, after the ancestral species has split into two populations |
|
House finches were found only in western North America until 1939, when a few individuals were released in New York City. These individuals established a breeding population and gradually expanded their range. The western population also expanded its range somewhat eastward, and the two populations have recently come in contact. If the two forms were unable to interbreed when their expanding ranges met, it would be an example of _____. |
a. allopatric speciation |
|
Most causes of speciation are relatively slow, in that they may take many generations to see changes, with the exception of _____. |
b. polyploidy |
|
Use the following description to answer the question(s) below. On the volcanic, equatorial West African island of Sao Tomé, two species of fruit fly exist. Drosophila yakuba inhabits the island’s lowlands, and is also found on the African mainland, located about two hundred miles away. At higher elevations, and only on Sao Tomé, is found the very closely related Drosophila santomea. The two species can hybridize, though male hybrids are sterile. A hybrid zone exists at middle elevations, though hybrids there are greatly outnumbered by D. santomea. Studies of the two species’ nuclear genomes reveal that D. yakuba on the island is more closely related to mainland D. yakuba than to D. santomea (2n = 4 in both species). Sao Tomé rose from the Atlantic Ocean about fourteen million years ago. Using only the information provided in the paragraph, which of the following is the best initial hypothesis for how D. santomea descended from D. yakuba?
a. habitat differentiation |
a. habitat differentiation |
|
Use the following description to answer the question(s) below. On the Bahamian island of Andros, mosquitofish populations live in various, now-isolated, freshwater ponds that were once united. Currently, some predator-rich ponds have mosquitofish that can swim in short, fast bursts; other predator-poor ponds have mosquitofish that can swim continuously for a long time. When placed together in the same body of water, the two kinds of female mosquitofish exhibit exclusive breeding preferences. Which two of the following have operated to increase divergence between mosquitofish populations on Andros? 1. improved gene flow |
a. 3 and 5 |
|
Hybrid zones provide an opportunity to investigate _____. |
d. the evolution of reproductive isolation |
|
How long does it take new species to form on Earth? |
b. The time required varies considerably. |
|
A certain species of salamander was split into two populations by a wide, dry valley, and the populations began to diverge from each other. After a period of time, some members of the two populations began to interbreed in a hybrid zone at the southern end of the valley. Only weak reproductive barriers existed by this time, so the two populations could freely interbreed and re-establish gene flow. This outcome in a hybrid zone is known as _____. |
b. fusion |
|
Reinforcement is most likely to occur when _____. |
d. hybrids have lower fitness than either parent population |
|
The phenomenon of fusion is likely to occur when, after a period of geographic isolation, two populations meet again and _____. |
b. an increasing number of viable, fertile hybrids is produced over the course of the next one hundred generations |
|
A hybrid zone is properly defined as _____. |
b. an area where mating occurs between members of two closely related species, producing viable offspring |
|
Hox genes are thought to play an important role in the development of different morphologies because _____. |
d. they provide positional information in the embryo |
|
If an organism has a relatively large number of Hox genes in its genome, it most likely _____. |
b. has a relatively complex anatomy |
|
Evolution works by _____. |
b. "tinkering" with existing structures |
|
Many species of snakes lay eggs. However, in the forests of northern Minnesota, where growing seasons are short, only live-bearing snake species are present. This trend toward species that have live birth in a particular environment is an example of _____. |
d. species selection |
|
The following question are based on the observation that several dozen different proteins comprise the prokaryotic flagellum and its attachment to the prokaryotic cell, producing a highly complex structure. If the complex protein assemblage of the prokaryotic flagellum arose by the same general processes as those of the complex eyes of molluscs (such as squids and octopi), then _____. a. neither eyes nor flagella could have arisen by evolution because both are too complex to have evolved |
b. ancestral versions of this protein assemblage were either less functional or had different functions than modern prokaryotic flagella |
|
Miller and Urey’s experiments that attempted to recreate conditions on early Earth were significant because _____. |
e. they showed that organic molecules such as amino acids could be produced from inorganic molecules |
|
Why do some scientists believe that RNA, rather than DNA, was the first genetic material? |
a. RNA has both information storage and catalytic properties. |
|
Earth probably formed _____ years ago, and the first life evolved as early as _____ years ago. |
e. 4.5 billion years ago … 3.9 billion years ago |
|
Which of the following is the correct sequence of events in the origin of life? |
b. II, III, I, IV |
|
The first genetic material on Earth was probably _____. |
c. self-replicating RNA molecules |
|
Several scientific laboratories across the globe are involved in research concerning the origin of life on Earth. Which of these questions is currently the most problematic and would have the greatest impact on our understanding if we were able to answer it? |
a. How did RNA sequences come to carry the code for amino acid sequences? |
|
One hypothesis that has been proposed regarding the origin of life suggests that life evolved from an "RNA world" to todays "DNA world." Considering the properties of RNA and DNA molecules, which questions would direct an investigation of the most insightful test(s) of this hypothesis? |
a. Could RNA have provided a template for DNA assembly, thereby enabling a more stable molecule that is replicated more accurately? |
|
The oldest fossils usually _____. a. are found in sediments formed during the Cenozoic era |
b. are found in the deepest strata |
|
Radiometric dating _____. a. can be used to directly date fossils in sedimentary rock |
b. allows us to indirectly date fossils up to billions of years old based on minerals in surrounding volcanic strata |
|
The earliest organisms were most likely _____. |
e. prokaryotic |
|
The atmosphere of early Earth probably contained no O2 until the emergence of organisms that _____. |
b. used water as an electron source for photosynthesis |
|
For many years scientists believed that almost all animal lineages burst into being during the Cambrian era (just after the end of the Precambrian super eon). However, there have been many recent findings of animal-like fossils and "trace fossils" (fossils of an animal-like organisms movement) from the late Precambrian. Which of the following best explains why it took so long to realize there was animal-like life in the Precambrian? |
d. Animals from the late Precambrian had soft bodies. |
|
Which listing of geological periods is in the correct order, from oldest to most recent? |
d. Cambrian, Devonian, Permian, Cretaceous |
|
For many years scientists believed that almost all animal lineages burst into being during the Cambrian era (just after the end of the Precambrian super eon). However, there have been many recent findings of animal-like fossils and "trace fossils" (fossils of an animal-like organisms movement) from the late Precambrian. Which of the following best explains why it took so long to realize there was animal-like life in the Precambrian? |
c. Animals from the late Precambrian had soft bodies. |
|
You are the lucky student of a wacky professor who develops a time machine. He asks if you will test it with him. You get in and there is an immediate glitch-the date readout fails so that when you land you are not sure what era you are in. Your professor begins to panic, but you see something that tells you are in the Cenozoic era. Which of the following could it be? |
c. a rabbit eating a daisy |
|
Endosymbiosis is an evolutionary theory that explains the origin of eukaryotes and suggests a specific order in which this might have occurred. Ancestral cells engulfed and then began to use the metabolic processes of the smaller cells. Based on shared core processes and features, which statement most accurately describes the order, the theory and the evolutionary implications for all organisms within domain Eukarya? |
a. As Earth was becoming more aerobic, mitochondria would have provided an advantage to host cells by converting "toxic" oxygen into energy for heterotrophic cells. Since mitochondria are found in all eukaryotes, these combinations likely evolved first. Photosynthetic eukaryotes probably acquired an autotrophic prokaryote, which developed an advantageous symbiotic relationship with the host cell. |
|
How does continental drift affect living organisms? |
e. All but one of these are correct. |
|
The oxygen revolution changed Earth’s environment dramatically. Which of the following took advantage of the presence of free oxygen in the oceans and atmosphere? a. the evolution of multicellular eukaryotic colonies from communities of prokaryotes |
c. the evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules |
|
Fossilized stromatolites a. formed around deep-sea vents. |
c. resemble structures formed by bacterial communities that are found today in some warm, shallow, salty bays. |
|
Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception. a. evolutionary innovation |
c. genetic drift |
|
Which statement about natural selection on early Earth is correct? a. Natural selection could act on a population of proto-cells on early Earth, selecting for those that were stable and had self-replicating, catalytic RNA that allowed them to grow and divide to produce similar daughter proto-cells. |
a. Natural selection could act on a population of proto-cells on early Earth, selecting for those that were stable and had self-replicating, catalytic RNA that allowed them to grow and divide to produce similar daughter proto-cells. |
|
A paleontologist finds a new tyrannosaur in a site she is excavating, and wishes to date the fossil. What is the most likely method she will use? a. She will measure the amount of the radioisotope uranium-238 in the stratum where she found the tyrannosaur. |
c. She will infer the age of the fossil by dating layers of volcanic rock above and below the stratum containing the fossil. |
|
Which of the following statements supports the hypothesis of "an RNA world" on early Earth? a. Some RNA molecules are important catalysts in modern cells. |
a. Some RNA molecules are important catalysts in modern cells. |
|
All animals can trace their lineage to a common ancestor that lived in the _____. a. Devonian |
e. Neoproterozoic era |
|
The earliest ancestors of about half of all extant animal phyla can be traced back to the _____ explosion. a. Carboniferous |
b. Cambrian |
|
Evidence of which structure or characteristic would be most surprising to find among fossils of the Ediacaran fauna? a. embryos |
c. hard parts |
|
Which statement is most consistent with the hypothesis that the Cambrian explosion was caused by the rise of predator-prey relationships? The fossil record reveals an increased incidence of _____. a. hard parts |
a. hard parts |
|
Whatever its ultimate cause(s), the Cambrian explosion is a prime example of _____. a. adaptive radiation |
a. adaptive radiation |
|
Arthropods invaded land about 100 million years before vertebrates did so. This most clearly implies that _____. a. arthropods evolved before vertebrates did |
c. arthropods have had more time to coevolve with land plants than have vertebrates |
|
The predatory bacterium Bdellovibrio bacteriophorus drills into a prey bacterium and, once inside, digests it. In an attack upon a Gram-negative bacterium that has a slimy cell covering, what is the correct sequence of structures penetrated by B. bacteriophorus on its way to the prey’s cytoplasm? a. 4, 1, 3, 2 |
a. 4, 1, 3, 2 |
|
Jams, jellies, preserves, honey, and other foods with high sugar content hardly ever become contaminated by bacteria, even when the food containers are left open at room temperature. This is because bacteria that encounter such an environment ____. a. undergo death as a result of water loss from the cell |
a. undergo death as a result of water loss from the cell |
|
Use the information in the following paragraph to answer the question(s) below. A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Fecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan.
This bacterium’s ability to survive in a human who is taking penicillin pills may be due to the presence of _____. a. 2 or 3 |
b. 2, 4, or 5 |
|
Use the information in the following paragraph to answer the question(s) below. A hypothetical bacterium swims among human intestinal contents until it finds a suitable location on the intestinal lining. It adheres to the intestinal lining using a feature that also protects it from phagocytes, bacteriophages, and dehydration. Fecal matter from a human in whose intestine this bacterium lives can spread the bacterium, even after being mixed with water and boiled. The bacterium is not susceptible to the penicillin family of antibiotics. It contains no plasmids and relatively little peptidoglycan.
In which feature(s) should one be able to locate a complete chromosome of this bacterium? a. 4 only |
c. 3 and 4 |
|
How does the large amount of genetic variation observed in prokaryotes arise? a. The mutation rate in prokaryotes is much higher than in eukaryotes. |
e. The second and third answers are correct. |
|
Which of the following is true of generalized bacteriophage transduction? a. The bacteriophage must enter the lysogenic cycle. |
b. The bacteriophage packages fragments of bacterial DNA into new phage particles. |
|
Why has the kingdom Protista been abandoned? a. Some protists are multicellular. |
e. The second and third answers are correct. |
|
Which of the following is true of secondary endosymbiosis? a. It is indicated by the presence of a double membrane surrounding the endymbiont. |
d. An organism containing an endosymbiont is engulfed by another organism and becomes an endosymbiont. |
|
According to the endosymbiotic theory, why was it adaptive for the larger (host) cell to keep the engulfed cell alive, rather than digesting it as food? a. The engulfed cell provided the host cell with adenosine triphosphate (ATP). |
a. The engulfed cell provided the host cell with adenosine triphosphate (ATP). |
|
All protists are _____. a. unicellular |
d. eukaryotic |
|
An individual mixotroph loses its plastids, yet continues to survive. Which of the following most likely accounts for its continued survival? a. It has an endospore. |
c. It engulfs organic material by phagocytosis or by absorption. |
|
A graduate student finds an organism in a pond and thinks it is a freshwater sponge. A postdoctoral student thinks it looks more like an aquatic fungus. How can they decide whether it is an animal or a fungus? a. See if it reproduces sexually. |
d. Look for cell walls under a microscope. |
|
A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom. Assuming that none of the following genes is absolutely conserved, which of the following would be the best choice on which to base the phylogeny? a. collagen genes |
a. collagen genes |
|
Which of the following is (are) unique to animals? a. flagellated gametes |
d. nervous system signal conduction and muscular movement |
|
What do animals ranging from corals to monkeys have in common? a. number of embryonic tissue layers |
c. presence of Hox genes |
|
Which of the following would you classify as something other than an animal? a. choanoflagellates |
a. choanoflagellates |
|
Among protostomes, which morphological trait has shown the most variation? |
b. type of body cavity |
|
What do all deuterostomes have in common? |
c. The pore (blastopore) formed during gastrulation becomes the anus. |
|
Select the correct statement about the evolution of animals. a. Approximately half the phyla of living organisms are found in Cambrian sediments. |
c. The oldest generally accepted fossils of large animals range in age from 565 to 550 million years old. |
|
Identify the features that distinguish animals from organisms in other multicellular kingdoms. a. Animals are ingestive heterotrophs. |
a. Animals are ingestive heterotrophs. |
|
Select the correct statement(s) about animal body plans. a. Development in all animals is determined by the unique family of Hox genes (or other similar homeobox genes). |
a. Development in all animals is determined by the unique family of Hox genes (or other similar homeobox genes). |
|
What is the key difference between a coelom and a pseudocoelom? a. Pseudocoeloms arose early in animal evolution and evolved into coeloms. |
b. Only a coelom is fully lined with mesoderm tissue. |
|
Which feature of deuterostome development explains the formation of identical human twins? a. In deuterostomes, the blastopore becomes the anus. |
b. Deuterostomes have indeterminate development. |
|
Which of these primate groups is most closely related to humans? a. apes |
a. apes |
|
_____ are the oldest known primate group. a. Apes |
b. Prosimians |
|
Which of the following statements about hominin evolution is correct? As hominins have evolved, _____. a. sexual dimorphism was significantly reduced |
a. sexual dimorphism was significantly reduced |
|
In what respect do hominins differ from all other anthropoids? |
c. bipedal posture |
|
Arrange the following taxonomic terms in order from most inclusive (most general) to least inclusive (most specific). a. 5, 1, 4, 2, 3 |
d. 5, 4, 1, 2, 3 |
|
Which of these traits is most strongly associated with the adoption of bipedalism? a. repositioning of foramen magnum |
a. repositioning of foramen magnum |
|
Which of the following statements about human evolution is correct? |
c. The upright posture and enlarged brain of humans evolved separately. |
|
With which of the following statements would a biologist be most inclined to agree? |
c. Humans and other apes represent divergent lines of evolution from a common ancestor. |
|
Which of the following statements describing hominin evolution is/are correct? |
b. Homo sapiens is the only surviving member of a highly branched evolutionary tree of hominin species. |
|
Of the following, which is the most inclusive level of organization in nature? a. community |
c. biosphere |
|
Which of the following causes Earth’s seasons? a. Earth’s tilt on its axis |
a. Earth’s tilt on its axis |
|
Which of the following investigations is an example of the study of an abiotic factor? a. identifying food sources for an egret population |
e. investigating how the amount of annual precipitation affects the distribution of a tree species. |
|
Which level of ecological study focuses the most on abiotic factors? a. speciation ecology |
d. ecosystem ecology |
|
Which of the following might be an investigation of microclimate? a. competitive interactions between various species of songbirds during spring migration |
b. the effect of sunlight intensity on species composition in a decaying rat carcass |
|
Which of the following choices includes all of the others in creating global terrestrial climates? a. differential heating of Earth’s surface |
a. differential heating of Earth’s surface |
|
The main reason polar regions are cooler than the equator is that _____. a. the polar atmosphere is thinner and contains fewer greenhouse gases |
d. sunlight strikes the poles at a lower angle. |
|
As climate changes because of global warming, plant species’ ranges in the northern hemisphere may move northward. The trees that are most likely to avoid extinction in such an environment are those that _____. a. produce well-provisioned seeds |
d. have seeds that are easily dispersed by wind or animals. |
|
Generalized global air circulation and precipitation patterns are caused by _____. a. rising, warm, moist air masses that cool and release precipitation as they rise and then, at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics |
a. rising, warm, moist air masses that cool and release precipitation as they rise and then, at high altitude, cool and sink back to the surface as dry air masses after moving north or south of the tropics |
|
When climbing a mountain, we can observe transitions in biological communities that are analogous to the changes _____. a. in biomes at different latitudes |
a. in biomes at different latitudes |
|
Which aspects of a region’s climate have the most impact on plants and animals? |
c. Temperature and moisture |
|
What are rain shadows? |
d. Dry regions on the leeward side of mountain ranges. |
|
In most cases, the two major climatic factors affecting the distribution of organisms in terrestrial ecosystems are _____. |
d. water and temperature |
|
What is a biome? |
a. a major type of ecosystem |
|
In the models that describe population growth, r stands for _____. |
b. per capita population growth rate. |
|
True or false? Factors that determine the per capita rate of increase of a population include the age of breeding and the number of offspring produced each year. |
a. True |
|
Which factor does not affect a habitat’s carrying capacity? |
d. Maximum number of individuals in a population. |
|
Which equation represents the logistic growth rate of a population? |
c. ΔNΔt=rMmaxN(K−N)K |
|
Which of the following statements about density-independent growth is true? |
b. Density-independent growth is also known as exponential growth. |
|
Under which of the following conditions would a population most likely experience exponential growth? |
d. Young populations with few individuals. |
|
Which of the following statements about a population experiencing logistic growth is true? a. If N is greater than K, the population will shrink. |
a. If N is greater than K, the population will shrink. |
|
A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Calculate an estimate of the total number of individuals added to (or lost from) a population of 1000 individuals in one year. a. 120 individuals added |
d. 40 individuals added |
|
During exponential growth, a population always _____. a. grows at its maximum per capita rate |
a. grows at its maximum per capita rate. |
|
Consider two old-growth forests: one is undisturbed while the other is being logged. In which region are species likely to experience exponential growth, and why? |
a. Logged, because the disturbed forest affords more resources for increased specific populations to grow. |
|
Which of these was the first of the major events that stimulated an increase in the size of the human population? |
d. the advent of agriculture |
|
Which of these was the second of the major events that stimulated an increase in the size of the human population? |
c. the Industrial Revolution |
|
Currently, how large is the worldwide population of humans relative to Earth’s carrying capacity for humans? |
c. There is insufficient information to answer this question. |
|
Which of the following statements regarding the future of populations in developing countries are correct? |
d. only II, III, and IV |
|
Which of the following statements about human population in industrialized countries is incorrect? |
b. Life history is r-selected. |
|
Which pair of terms most accurately describes life history traits for a stable population of wolves? a. semelparous; r-selected |
b. iteroparous; K-selected |
|
The observation that members of a population are uniformly distributed suggests that |
d. the members of the population are competing for access to a resource. |
|
A population’s carrying capacity |
a. may change as environmental conditions change. |
|
Population ecologists follow the fate of same-age cohorts to |
e. determine the birth rate and death rate of each group in a population. |
|
Consider a population whose growth over a given time period can be described by the exponential model: dN/dt = rN. Select the correct statement about this population. |
c. A population with a positive value of r will grow exponentially. |
|
Consider a population whose growth can be described by the logistic growth model: dN/dt = rmaxN[(K − N)/K]. Which of the following statements about this population is true? |
a. At low values of N, the logistic growth and exponential growth (dN/dt = rN) models predict similar population growth. |
|
Select the correct statement about the global carrying capacity for the human population. |
b. Estimates of the global carrying capacity for the human population depend on resource use per capita. |
|
According to the principle of competitive exclusion, two species cannot continue to occupy the same _____. a. range |
c. ecological niche |
|
The term used to describe a harmless organism resembling a harmful one is _____. a. warning coloration |
d. Batesian mimicry |
|
An organism’s "trophic level" refers to _____. a. whether it is early or late in ecological succession |
e. its food source |
|
Keystone species’s absence would cause a major disruption in a community. |
True. |
|
Which of the following best illustrates ecological succession? |
a. Grass grows on a sand dune, is replaced by shrubs, and then by trees. |
|
The principle of competitive exclusion states that |
a. two species that have exactly the same niche cannot coexist in a community. |
|
Fundamental Niche versus Realized niche |
The fundamental niche is the entire set of conditions of an area that the animal is supposed to occupy. The realized niche is the set of conditions of an area that the animals does occupy presently. |
|
Select the correct statement(s) about a terrestrial food chain. a. Energy is transferred from decomposers to plants to herbivores to carnivores. |
b. About 1% of the energy stored in producers is converted to organic matter at the secondary consumer level. |
|
Select the correct statement(s) about the transfer of food energy up the trophic levels from its source in autotrophs. a. An organism feeds at only one trophic level. |
b. The length of a food chain is limited by the inefficiency of energy transfer along the chain. |
|
Which of the following may result from resource partitioning? a. Competing species may partition time, feeding at different times of day. |
a and c |
|
What is a likely outcome of a moderate disturbance, such as a severe thunderstorm? a. Loss of an equilibrium state of balance, leading to a less healthy community |
c. Patches of different habitats within the landscape. |
|
To survive, all animals must _____. |
a. balance consumption of food with use and storage of nutrients |
|
The "essential nutrients" for proper human nutrition include _____. |
a. calcium, sodium, potassium, and other minerals |
|
Birth defects of the neural tube in humans _____. |
c. are reduced from about 6% without folic acid supplements in the periconception interval to about 1% when the supplements were taken |
|
In a well-fed human eating a Western diet, the richest source of stored chemical energy in the body is _____. |
a. fat in adipose tissue |
|
What is the importance of consuming an adequate amount of proteins in the diet? |
c. Proteins serve a variety of functions, and the body does not store excess quantities of protein. |
|
Choose the list that presents the four stages of food processing in the order in which they naturally occur. |
e. ingestion → digestion → absorption → elimination |
|
In the digestive system, peristalsis is _____. |
b. smooth muscle contractions that move food along the esophagus |
|
Historically inaccurate diagnosis of acid reflux disorders and gastric ulcers has been improved by _____. |
d. screening for H. pylori infections |
|
Over-the-counter medications for acid reflux or heartburn block the production of stomach acid. Which of the following cells are directly affected by this medication? a. goblet cells |
b. parietal cells |
|
The pancreas is involved in the digestion of _____. |
d. I, II, III, and IV |
|
The bile salts _____. |
a. emulsify fats in the duodenum |
|
Constipation can result from the consumption of a substance that _____. |
d. promotes water reabsorption in the large intestine |
|
When a woman has her gallbladder removed, she should probably reduce her consumption of _____. |
a. fats |
|
Different types of food are eaten by various groups of animals, but it is usually true that _____. a. cellulose digestion in ruminant mammals occurs before the ingested foods reach the small intestine |
a. cellulose digestion in ruminant mammals occurs before the ingested foods reach the small intestine |
|
Secretin stimulates the _____ to secrete _____. a. pancreas … bicarbonate |
a. pancreas … bicarbonate |
|
The acidity of the stomach contents triggers the small intestine to secrete a hormone known as _____. a. cholecystokinin, or CCK |
d. secretin |
|
Bile is produced by the _____ and stored by the _____ until it is secreted into the small intestine. a. liver … gall bladder |
a. liver … gall bladder |
|
Cattle are able to survive on a diet consisting almost entirely of plant material because cattle _____. a. manufacture all fifteen amino acids out of sugars in the liver |
c. have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs |
|
An enlarged cecum is typical of _____. a. rabbits, horses, and herbivorous bears |
a. rabbits, horses, and herbivorous bears |
|
If you were to jog one kilometer a few hours after lunch, which stored fuel would you probably tap? a. blood proteins |
c. liver glycogen and muscle glycogen |
|
In a healthy person, after a large meal, the production of _____ will increase. After fasting, the production of _____ will increase. a. trypsin; trypsinogen |
b. insulin; glucagon |
|
Fat digestion yields fatty acids and glycerol, whereas protein digestion yields amino acids. Both digestive processes __________. |
d. add a water molecule to break bonds |
|
The mammalian trachea and esophagus both connect to the a. rectum. |
c. pharynx |
|
Which of the following organs is incorrectly paired with its function? a. stomach-protein digestion |
c. large intestine-bile production |
|
Which of the following is not a major activity of the stomach? a. enzyme secretion |
d. nutrient absorption |
|
Many people have a tendency to gorge on rich, fatty foods. How could such a preference have evolved? |
c. In ancestral hunter-gatherer communities, individuals with a tendency to gorge on such foods when available would have had a selective advantage. |
|
Identify the roles played by human gut bacteria. |
b. Ulcers are caused by the acid-tolerant bacterium Helicobacter pylori. |
|
Bacteria in the human gut are which of the following? a. all pathogens |
b. both pathogens and mutualists |
|
Select the correct statement about essential nutrients. a. Due to their biochemical sophistication, humans have to ingest fewer essential nutrients than do other animals. |
c. Essential nutrients must be obtained from diet. |
|
The bed of capillaries in a vertebrate kidney where water, urea, and salts are filtered out of the blood is the __________. a. glomerulus b. Bowman’s capsule c. collecting duct d. loop of Henle e. proximal convoluted tubule |
a. glomerulus |
|
In which of the following portions of a nephron of the mammalian kidney does the filtrate have the highest osmolarity? a. Descending limb of the loop of Henle in the inner medulla b. Bowman’s capsule c. Proximal tubule d. Distal tubule e. Collecting duct in the cortex |
a. Descending limb of the loop of Henle in the inner medulla |
|
Which type of organism would have the least chance of long-term survival in the given environment? a. Stenohaline animals that move between fresh water and seawater b. Osmoconformers in seawater c. Euryhaline animals in fresh water d. Osmoregulators in seawater e. Euryhaline animals in seawater |
a. Stenohaline animals that move between fresh water and seawater |
|
Which of the following animals is paired with the correct excretory system unit? a. Bird; kidney b. Fish; metanephridia c. Insect; protonephridia d. Flatworm; Malpighian tubule e. Earthworm; protonephridia |
a. Bird; kidney |
|
Which animal would most likely be an osmoconformer? a. Starfish (sea star) b. Sea trout c. Cane toad d. Seagull e. All of the listed responses are correct. |
a. Starfish (sea star) |
|
Which of the following have an excretory system that functions without a filtration step? a. Insects b. Flatworms c. Earthworms d. Marine fishes e. Freshwater fishes |
a. Insects |
|
As filtrate passes through the long loop of Henle, salt is removed and concentrated in the interstitial fluid of the kidney medulla. Because of this high salt concentration, the nephron is able to __________. a. establish a hyperosmotic interstitial medullary concentration b. excrete the maximum amount of salt c. neutralize toxins that might accumulate in the kidney d. control the pH of the interstitial fluid e. excrete a large amount of water |
a. establish a hyperosmotic interstitial medullary concentration |
|
All of the following processes occur in the nephron of the kidney except ________. blood cell formation tubular secretion capsular filtration cellular respiration selective reabsorption |
blood cell formation |
|
Which of the following would not normally pass into a nephron of the kidney as a component of the filtrate? Lymphocytes Salts Glucose Vitamins Nitrogenous wastes |
Lymphocytes |
|
An animal would lose water to its environment through osmosis under which set of conditions? Body fluids of 400 mOsm/L in an environment of 1,000 mOsm/L Body fluids of 1,100 mOsm/L in an environment of 1,000 mOsm/L Body fluids of 1,000 mOsm/L in an environment of 1,000 mOsm/L Body fluids of 400 mOsm/L in an environment of 300 mOsm/L Body fluids of 900 mOsm/L in an environment of 500 mOsm/L |
Body fluids of 400 mOsm/L in an environment of 1,000 mOsm/L |
|
Which of the following is a tube that carries urine from the kidneys to the urinary bladder in a mammal? Ureter Loop of Henle Urethra Distal tubule Proximal tubule |
Ureter |
|
Osmoregulation in a freshwater fish would not include ___________. drinking large amounts of water gaining water and some ions in food uptake of salt ions by gills osmotic water gain through gills excreting salt ions and large amounts of water in dilute urine |
drinking large amounts of water |
|
Which of the following substances is generally filtered from the blood by the kidneys? All of the listed responses are correct. Water Sodium Urea Glucose |
All of the above |
|
What is the correct path of filtrate through a nephron of the kidney as it is processed into urine? a. Bowman’s capsule, proximal tubule, descending limb of loop of Henle, thin segment of ascending limb, thick segment of ascending limb, distal tubule, collecting duct b. Collecting duct, descending limb of loop of Henle, thick segment of ascending limb, thin segment of ascending limb, proximal tubule, distal tubule, Bowman’s capsule c. Collecting duct, Bowman’s capsule, descending limb of loop of Henle, thick segment of ascending limb, thin segment of ascending limb, proximal tubule, distal tubule d. Bowman’s capsule, proximal tubule, distal tubule, descending limb of loop of Henle, thick segment of ascending limb, thin segment of ascending limb, collecting duct e. Proximal tubule, descending limb of loop of Henle, thick segment of ascending limb, thin segment of ascending limb, distal tubule, collecting duct, Bowman’s capsule |
a. Bowman’s capsule, proximal tubule, descending limb of loop of Henle, thin segment of ascending limb, thick segment of ascending limb, distal tubule, collecting duct |
|
Humans excrete: |
1. Urea 2. ammonia 3. uric acid |
|
Most of our nitrogen-containing waste products are a result of __________. protein metabolism drug use consumption of foods high in nitrates, such as green vegetables the body’s attempts to maintain pH homeostasis metabolism of fatty foods |
protein metabolism |
|
Under normal conditions, a pair of human kidneys processes what volume of blood each day? |
1,600 L |
|
Isosmotic relative to environment experience: |
no net water loss by osmosis |
|
juxtamedullary nephron vs. cortical nephron |
juxtamedullary is longer and goes deeper into the inner medulla of the kidney |
|
Which of the following would be most likely to increase for an amphibian moving from the aquatic habitat it occupies as a larva to the terrestrial habitat it occupies as an adult? Energetic cost of excretion Volume of urine produced Osmotic water gain Excretion of salt Excretion of ammonia |
Energetic cost of excretion |
|
longer loop of Henle means: |
more water absorption. beneficial in water |
|
What is the source of the filtrate produced in Bowman’s capsule? Blood in capillaries Urine Lymphatic fluid Cells of the kidney The loop of Henle |
Blood capillaries |
|
Which of the following is not moved out of or into the filtrate of a nephron through active transport by epithelial cells? Water Nutrients NaCl H+ K+ |
water |
|
Chloride cells in the gills of marine bony fishes play a role in which step of excretory system function? Excretion Filtration Reabsorption Secretion All of the listed responses are correct. |
excretion |
|
Plants must always compromise between _____ and _____. |
a. maximizing photosynthesis … minimizing water loss |
|
Mycorrhizae are _____. |
structures that minimize water loss from leaves |
|
Given that early land plants most likely share a common ancestor with green algae, the earliest land plants were most likely _____. |
b. nonvascular plants that grew leafless, photosynthetic shoots |
|
A fellow student brought in a leaf to be examined. The leaf was dark green, thin, had stoma on the lower surface only, and had a total surface area of ten square meters. Where is the most likely environment where this leaf was growing? |
b. a tropical rain forest |
|
The _____ is the most efficient route of water movement in plants, while the _____ is the most select. |
d. apoplast; transmembrane |
|
Which structure or compartment is separate from the apoplastic route? a. the cell wall of a root hair |
d. the lumen of a sieve tube |
|
When an animal cell is placed in a hypotonic solution and water enters the cell via osmosis, the volume of the cell increases until it bursts. This does not happen to plant cells, because _____. |
d. they have cell walls, which provide pressure to counteract the pressure of the incoming water |
|
How does a flaccid cell differ from a turgid cell? |
A flaccid cell has lower pressure potential. |
|
Compared to a cell with few aquaporins in its membrane, a cell containing many aquaporins will _____. |
have a faster rate of osmosis |
|
Which tissue acts as a filter on the water absorbed by root hairs? |
endodermis |
|
True or false? Root pressure can move water a long distance up the xylem because of the higher water potential of the xylem in comparison to the water potential in the surrounding cells. |
false |
|
Which of the following statements about the distribution of sap throughout a plant is true? |
The mechanism that explains the movement of sugars throughout a plant is called the pressure-flow hypothesis. |
|
Which term describes an area where sugars are used or stored? |
sink |
|
Which of the following statements about xylem transport is true? |
Water and minerals move through the root cortex into the xylem and upward through the stem and into leaves. |
|
What characterizes the rates of photosynthesis and transport in a plant on a dry cloudy day? |
Both the photosynthesis and transpiration rates are low. |
|
Loss of water from the aerial parts of plants is called _____. gas exchange |
transpiration |
|
What is the main force by which most of the water within xylem vessels moves toward the top of a tree? |
evaporation of water through stoma |
|
Xerophytes minimize water loss by _____. reducing the thickness of the leaf cuticle |
using the CAM pathway |
|
The opening of stomata is thought to involve _____. active transport of water out of the guard cells |
an increase in the solute concentration of the guard cells |
|
Ignoring all other factors, what kind of day would result in the fastest delivery of water and minerals to the leaves of an oak tree? very hot, dry, windy day |
very hot, dry, windy day |
|
The water lost during transpiration is a side effect of the plant’s exchange of gases. However, the plant derives some benefit from this water loss in the form of _____. increased turgor and increased growth |
evaporative cooling and mineral transport |
|
Which of the following is a correct statement about a difference between xylem and phloem transport? |
Xylem sap moves up; phloem sap moves up or down. |
|
The solute most abundant in phloem sap is _____. sugar |
sugar |
|
Arrange the following five events in an order that explains the mass flow of materials in the phloem. 2, 4, 3, 1, 5 |
2, 4, 3, 1, 5 |
|
Water flows into the source end of a sieve tube because _____. water pressure outside the sieve tube forces in water |
sucrose has been actively transported into the sieve tube, making it hypertonic |
|
Which of the following supports the finding that sugar translocation in phloem is an active (energy-requiring) process? Strong pH differences exist between the cytoplasm of the companion cell and the mesophyll cell. |
Sucrose occurs in higher concentrations in companion cells than in the mesophyll cells where it is produced. |
|
In the pressure-flow mechanism, loading of sucrose from companion cells to sieve-tube elements takes place through _____. facilitated diffusion |
plasmodesmata |
|
If a plant’s stomata are closed and no transpiration is occurring, which of the following predictions is accurate? |
Without transpiration, less water will be absorbed from the soil. |
|
Select the accurate statement about water potential. Adding solutes to water increases water potential. |
Water in a turgid cell has positive pressure potential. |
|
The glia present throughout the vertebrate brain or spinal cord that surround axons and speed up electrical signals are called __________. oligodendrocytes Schwann cells astrocytes microglia all of the listed responses are correct |
oligodendrocytes |
|
Which of the following statements is an accurate description of animal cognition? Some birds can understand abstract concepts such as numbers. Mammals are the only animals considered to have cognitive abilities. Cognition depends on a highly convoluted cerebral cortex. Cognition is primarily a result of processes occurring in the hippocampus. All species rely on the same brain region for cognition. |
Some birds can understand abstract concepts such as numbers. |
|
Which of the following is an action brought about by the sympathetic division of the autonomic nervous system? Relaxation of lung bronchi Increase in gallbladder activity Increase in salivation Constriction of pupils All of the listed responses are correct. |
Relaxation of lung bronchi |
|
Which of the following statements is an accurate description of the evolution of the vertebrate brain? Birds and mammals have evolved a proportionally larger forebrain than have other vertebrate groups. In humans, the midbrain occupies a larger proportion of the brain than it does in any other vertebrate group. Except for humans, vertebrates have maintained a relatively constant ratio of brain-to-body mass. Only mammals possess a forebrain, midbrain, and hindbrain. Regional specialization of the brain is apparent only in vertebrate groups that have proportionally smaller brains. |
Birds and mammals have evolved a proportionally larger forebrain than have other vertebrate groups. |
|
In humans, the part of the brain that increases in size and complexity most significantly during the second and third month of embryonic development is derived from the embryonic __________. forebrain forebrain and midbrain midbrain midbrain and hindbrain hindbrain |
forebrain |
|
Which of the following statements is an accurate description of sleep? Humans cannot live without sleep. The brain is largely inactive during sleep. Sleep occurs only in terrestrial animals. The brain does not receive external stimuli during sleep. Scientists currently lack any tools with which to investigate sleep. |
Humans cannot live without sleep. |
|
One of the functions of the __________ is monitoring breathing centers in the medulla. pons cerebrum hypothalamus thalamus cerebellum |
pons |
|
The pathway that a nervous signal travels in completing a typical vertebrate reflex is ____________. a. sensors; sensory neurons; interneurons of the spinal cord; motor neuron b. sensors; sensory neurons; interneurons of the spinal cord; brain; motor neuron c. brain; motor neuron; interneurons of the spinal cord; sensory neurons d. brain; interneurons of the spinal cord; motor neurons; sensory neurons; sensors e. sensors; interneurons of the spinal cord; motor neurons; sensory neurons; brain |
a. sensors; sensory neurons; interneurons of the spinal cord; motor neuron |
|
Taking illegal amphetamines ("speed") can induce symptoms similar to __________. schizophrenia Parkinson’s disease bipolar disorder Alzheimer’s disease none of the listed responses is correct |
schizophrenia |
|
Gray matter of the nervous system differs from white matter in that ____________. gray matter is primarily made up of neuron cell bodies, whereas white matter consists mainly of bundled axons gray matter makes up the brain, and white matter is found only in peripheral nerves gray matter makes up the brains of invertebrates, whereas white matter makes up the brains of vertebrates gray matter results from damage to white matter gray matter develops from white matter |
gray matter is primarily made up of neuron cell bodies, whereas white matter consists mainly of bundled axons |
|
The limbic system is involved in __________. emotion and memory speech and hearing vision sleep and wakefulness control of heartbeat and respiration |
emotion and memory |
|
Which of the following neurotransmitters is most closely associated with schizophrenia, addiction, and Parkinson’s disease? Dopamine β-amyloid Glutamate Amphetamine None of the listed responses is correct. |
dopamine |
|
A neuron that transmits an impulse to the central nervous system after the neuron is stimulated by the environment is called a(n) __________. sensory neuron motor neuron interneuron parasympathetic neuron sympathetic neuron |
sensory neuron |
|
Which would be present in an animal with a nerve net? Radial symmetry Nerves Fused ganglia Ganglia Central nervous system |
Radial symmetry |
|
Which of the following is caused by the death of neurons in the brain that release dopamine? Parkinson’s disease Schizophrenia Alzheimer’s disease Major depressive disorder None of the listed responses is correct |
Parkinson’s disease |
|
A physician friend of yours tells you about a patient with a head injury who suddenly stopped breathing during the examination. What portion of the brain was probably injured? Medulla oblongata Cerebrum Cerebellum Hypothalamus Pituitary |
Medulla oblongata |
|
Long-term potentiation (LTP) involves lasting changes in ____________. the strength of signal transmission across synapses the length of the axons the number of neurons the number of neuronal synapses the mass of the brain |
the strength of signal transmission across synapses |
|
Which of the following contributes to learning and memory storage in the brain? Excitatory neurotransmitters released from presynaptic neurons into synapses Repeated, weak stimulation of receiving neurons A decline in long-term potentiation A decreased concentration of calcium ions entering receiving neurons through calcium channels Inactivation of the AMPA glutamate receptor into the postsynaptic membrane |
Excitatory neurotransmitters released from presynaptic neurons into synapses |
|
Which of the following is a component of the vertebrate central nervous system (CNS)? All of the listed responses are correct. Brain Spinal cord Nerves Glia |
All of the listed responses are correct. |
|
An increase in the size of the hindbrain of vertebrates has been associated with an increased ability in ____________. rapid, complex movement reasoning olfaction vision hearing |
rapid, complex movement |
|
Which of the following statements is an accurate description of biological clocks? In an unchanging environment, there is little variation in the periodicity of the human biological clock. The consistency of a biological clock depends on sensory information indicating when it is day and night. In humans, daily activity cycles maintained by the biological clock are adjusted by the amygdala to match environmental conditions. A biological clock is an adaptation that first arose in vertebrates. Only humans have their physiology regulated by a biological clock. |
In an unchanging environment, there is little variation in the periodicity of the human biological clock. |
|
astrocytes |
blood-brain barrier |
|
In humans, the frontal lobe of the brain handles functions associated with ____________. decision making language comprehension hearing coordination of movement homeostasis |
decision making |
|
Individuals suffering from bipolar disorder ____________. experience periods of increased energy, overtalkativeness, and increased risk taking typically develop multiple personalities lack effective treatment options experience loss of motor control comprise 10% of the world’s population |
experience periods of increased energy, overtalkativeness, and increased risk taking |
|
The developing embryonic brain is shaped by __________. the selective elimination in neurons and synapses differences in the rates of blood vessel growth pressures exerted by the growing skull variations in the levels of nutrients received across the placenta an oxygen gradient that promotes growth where oxygen is most concentrated |
the selective elimination in neurons and synapses |
Share This
Flashcard
