Biology 1404 TTU Exam 2
A fish species known for its success in the aphotic zone may have which of the following characteristics? 1) Symbioses with photosynthetic organisms 2) Highly developed chemoreception 3) Adaptations for burrowing 4) Adaptations for sit-and-wait predation A) 2, 3, and 4 B) 1 and 2 C) 2 and 4 D) 1, 2, and 3 E) 1, 2, and 4
A) 2,3,4
If a population begins with 200 individuals and has 0.2 survivorship by age 10, how many individuals are left at age 10? A) 40 B) 20 C) 100 D) 2
A) 40
Of the total potential net primary productivity on the planet, humans are currently preventing or appropriating 24 percent of potential NPP. Of this percentage, how much is being directly utilized by humans? A) 53 percent B) 40 percent C) 65 percent D) 5 percent
A) 53 percent
Which of the following events best illustrates an adaptive radiation? A) A fishless lake is colonized by a single fish species, which over a few thousand years gives rise to several species, each with a series of unique feeding adaptations. B) A small group of tree-dwelling lizards of a single species migrates to an uninhabited, treeless island and adapts to use the open grassland habitat. C) A colonizing species of fruit fly takes up residence on a new continent and displaces two closely related native species. D) A population of a cricket species takes up residence in a cave. Over many generations, the cave crickets eventually lose their eyes, like many other cave-dwelling animals.
A) A fishless lake is colonized by a single fish species, which over a few thousand years gives rise to several species, each with a series of unique feeding adaptations.
Why does the 2009 U.S. population continue to grow even though the United States has essentially established a zero population growth (ZPG)? A) Immigration B) Baby boomer reproduction C) The 2007-09 economic recession D) Better sanitation E) Increased emigration
A) Immigration
A hypothetical island lies far from any other landmasses. There are many different types of plants, but only one animal, a beetle, that can fly or walk from plant to plant and that feeds by chewing leaves. Given that the beetle is not exploiting all of the resources on the island, which morphological change would be most likely to trigger an adaptive radiation of the beetles? A) A mouthpart that can pierce fruits and seeds B) A change in wing shape that improves flight speed C) An additional segment on a pair of legs
A) A mouthpart that can pierce fruits and seeds.
Which of the following statements is not true? A) According to the fossil record and phylogenetic analyses, angiosperms evolved before gymnosperms; angiosperms are the only land plants with vessels. B) Green algae in the lineage Charophyceae are the closest living relatives of land plants. C) Horsetails and ferns form a distinct lineage. They have vascular tissue but reproduce via spores, not seeds. D) The nonvascular plants form a monophyletic group.
A) According to the fossil record and phylogenetic analyses, angiosperms evolved before gymnosperms; angiosperms are the only land plants with vessels.
Which of the following statements most accurately explains why analogous traits are not informative for constructing phylogenetic trees? A) Analogous traits represent convergent evolution and do not represent synapomorphies that define monophyletic groups. B) Analogous traits define monophyletic groups because they define synapomorphies. C) Analogous traits typically evolve due to adaptations of different organisms to the same habitat (e.g., aquatic environments). Organisms in similar habitats are likely related phylogenetically. D) Analogous traits develop from homologous structures, and are therefore useful in constructing phylogenies.
A) Analogous traits represent convergent evolution and do not represent synapomorphies that define monophyletic groups.
Which of the following statements about seed plants is true? A) Angiosperms have more species diversity than other taxa of land plants. B) Seed plants lack vascular tissue. C) Angiosperms produce "naked seeds." D) Gymnosperms have more species diversity than other taxa of land plants
A) Angiosperms have more species diversity than other taxa of land plants.
If the sun were to suddenly stop providing energy to Earth, most ecosystems would vanish. Which of the following ecosystems would likely survive the longest after this hypothetical disaster? A) Benthic ocean B) Tropical rain forest C) Desert D) Grassland E) Tundra
A) Benthic Ocean
Which of the following leads to growth of a population? A) Births B) Lack of immigration C) Deaths D) Emigration
A) Births
What is the difference between logistic and exponential growth model predictions when population numbers become high? A) Both models are the same at low population densities, but when densities are high, the growth is reduced or stopped in the logistic model, whereas growth continues in the exponential model regardless of population density. B) Logistic models do not change the shape of their curve, but exponential models flatten out or even decline. C) Both logistic and exponential models respond to the approaching carrying capacity by reducing their growth rate, but logistic models reduce the growth rate more. D) The exponential model includes the effects of perturbations, but the logistic model does not.
A) Both models are the same at low population densities, but when densities are high, the growth is reduced or stopped in the logistic model, whereas growth continues in the exponential model regardless of population density.
What are population dynamics? A) Changes in populations through time and space B) Regular fluctuations in the population size of some animals C) The proportion of individuals at each possible age D) The number of individuals in a population born each year
A) Changes in populations through time and space
Why is carrying capacity not a fixed value? A) Conditions change in both space and time, making more or fewer resources available. B) Carrying capacity is a fixed value. C) The value is intrinsic to each species' rate of growth. D) Increased population size will reduce the carrying capacity.
A) Conditions change in both space and time, making more or fewer resources available.
The growing season would generally be shortest in which of the following biomes? A) Coniferous forest B) Savanna C) Temperate grassland D) Tropical rain forest E) Temperate forest
A) Coniferous forest
Of the many links in a nutrient cycle, which one most often limits the overall rate at which nutrients move through an ecosystem? A) Decomposition of detritus B) Animal consumption and conversion to tissue C) Plant and animal death and their addition to the dead biomass D) Plant nutrient uptake and conversion to tissue
A) Decomposition of detritus
Which statement about productivity is true? A) Energy can be converted to tissue. B) Production of biomass is highest at the highest trophic levels. C) All net primary productivity is available as food to herbivores. D) Gross primary productivity is that part of productivity unavailable as food to herbivores. E) Several species can be present in each trophic level.
A) Energy can be converted to tissue.
In a typical grassland community, which of the following is the primary consumer? A) Grasshopper (eats the grass) B) Snake (eats the shrew) C) Hawk (eats the snake) D) Grass (uses the sun's energy to produce biomass) E) Shrew (eats the grasshopper)
A) Grasshopper (eats the grass)
Species with high survivorship typically have _____________. A) high intrinsic rates of growth B) low fecundity C) small generation times D) large numbers of offspring
B) low fecundity
During the Zootoca vivipara study, researchers monitored individuals on a daily basis to document the number of young produced by each female in the wild. What would be the best way to obtain the same type of data but not have to visit the site every day? A) Install cameras on-site to monitor lizard activity. B) Capture animals twice per year and count them. C) Try the study in an isolated population in the lab. D) Capture animals and implant tracking devices.
A) Install cameras on-site to monitor lizard activity.
Why is it difficult to master alternation of generations? A) It does not occur in humans, and gamete formation results from mitosis, not meiosis, as it does in animals. B) Alternation of generations only exists when sex organs replicate in animals. C) Alternation of generations occurs when it goes through gametophytes and heterosexual channels. D) It occurs when meiosis takes place.
A) It does not occur in humans, and gamete formation results from mitosis, not meiosis, as it does in animals.
What is the advantage of a phylogenetic tree? A) It helps us to understand how species are related to each other. B) It helps us to think of new scientific hypotheses. C) It helps us to understand fossils. D) It helps us to understand animal behavior.
A) It helps us to understand how species are related to each other.
New Zealand lies between 36 degrees and 47 degrees south latitude and 165 degrees and 180 degrees east longitude. During which month would the weather be coldest and the days shortest? A) June B) September C) March D) December
A) June
Microphylls are found in which plant group? A) Lycophytes B) Mosses C) Whisk ferns D) Liverworts
A) Lycophytes
Which of these characteristics determines whether a plant is heterosporous? A) Male and female spores are morphologically distinct. B) It produces bisexual gametophytes. C) It has vascular tissue. D) Its diploid sporophyte produces spores via meiosis.
A) Male and female spores are morphologically distinct.
What is a pollen grain? A) Male gametophyte B) Male sporophyte C) Sperm D) Female gametophyte
A) Male gametophyte
What does the presence of a coal mine in an area indicate about that region's geologic history? A) Marshy, swampy, or boggy habitats were once found there. B) Water in this area was well oxygenated. C) Coal seams were likely available and exploited by native humans in the region thousands of years ago. D) Shallow seas were once located there.
A) Marshy, swampy, or boggy habitats were once found there.
By which process do gametophytes produce gametes? A) Mitosis B) Meiosis C) Diffusion D) Apoptosis
A) Mitosis
Gymnosperms and angiosperms have all of the following in common except __________. A) ovaries B) seeds C) pollen D) vascular tissue
A) Ovaries
All land plants have a life cycle featuring alternation of generations. Which statement best explains the similarities or differences in roles played by the following life cycle stages, all of which are visible to the naked eye and commonly seen in nature: pine trees, leafy ferns, beds of mosses, and flowering rose bushes. A)Rose bushes, ferns, and pine trees produce spores. The commonly visible stage of mosses releases gametes. B)All of these stages produce sperm and eggs. C)All of these stages release spores that develop into gametophytes. D)Structures on the ferns, roses, and pine trees release pollen that develops into the male gametophyte. Mosses do not produce pollen.
A) Rose bushes, ferns, and pine trees produce spores. The commonly visible stage of mosses releases gametes.
Why are most fossils found in sedimentary rock? A) Sedimentary rock is formed in habitats where there are high sedimentation rates. Anything that was deposited would be quickly buried, and decomposition would be low in the anoxic environment. B) Fossils form in sedimentary rock because they are dried out while exposed on the surface to the elements, and then are slowly covered with more sedimentary layers. C) Fossils typically form in moist tropical environments because that is where some of the highest levels of biodiversity can be observed. Because of the high number of organisms that live in these environments, it is likely that at least a small number of those organisms will be fossilized. D) Fossils form in sedimentary rock because it helps to harden soft body parts of certain organisms. This is why there are so many fossils of worms in the fossil record.
A) Sedimentary rock is formed in habitats where there are high sedimentation rates. Anything that was deposited would be quickly buried, and decomposition would be quickly buried, and decomposition would be low in the anoxic environment.
Which of the following statements about food webs is true? A) Several species can be present in each trophic level. B) The overall average number of trophic levels found in a food web is about seven. C) Food webs show which species are keystone species. D) A food web depicts a single species as it changes demographically.
A) Several species can be present in each trophic level.
Two different sites contain a variety of tree species. Site one has 202 tree species, while a same-size plot at site two has 12 tree species. Which of the following is most likely to be true? A) Site one is in a tropical rain forest, and site two is in a temperate deciduous forest. B) Both sites are in a boreal forest. C) Site one is in a temperate deciduous forest, and site two is in a tropical rain forest. D) Both sites are in a tropical rain forest.
A) Site one is in a tropical rain forest, and site two is in a temperate deciduous forest.
Select the correct statement about green algae. A) Some green algae form stable associations with fungi to produce lichens. B) Green algae are important primary producers only in near-shore ocean environments. C) Green algae have chloroplasts but lack mitochondria. D) Green algae synthesize starch in the mitochondria as a storage product of photosynthesis.
A) Some green algae form stable associations with fungi to produce lichens.
Plants must take in carbon dioxide from the atmosphere for photosynthesis, but the waxy substance that covers the plant to prevent water loss also prevents the exchange of gases. What structure found in modern plants is the solution to this problem? A)Stoma B) Tracheid C) Cuticle D) Spores encased in sporopollenin
A) Stoma
In areas of permafrost, stands of black spruce are frequently observed in the landscape, while other tree species are noticeably absent. Often, these stands are referred to as ʺdrunken forestsʺ because many of the black spruce are displaced from their normal vertical alignment, leaning to one side or another. What is the most likely explanation for the unusual growth of these forests in this marginal habitat? A) Taproot formation is impossible, so trees have developed shallow root beds. B) Needles have adapted to withstand cold arctic temperatures. C) Branches have adapted to absorb more carbon dioxide with this displaced alignment. D) Trees are tilted so snow prevents them from breaking or tipping over. E) Trees tip so that they do not compete with each other for sunlight.
A) Taproot formation is impossible, so trees have developed shallow root beds.
Which aspects of a region most influence where different types of plants exist? A) Temperature and moisture B) Moisture and wind C) Soil composition and temperature D) Sunlight and wind
A) Temperature and moisture
Which of the following statements is true of biomagnification? A) The concentration of toxin can more than double at each level of the food chain. B) Biomagnification is only a problem in terrestrial environments because the ocean dilutes toxins to a negligible level. C) Biomagnification is not an environmental problem. D) Biomagnification is more likely to occur for compounds that are easily excreted by consumers.
A) The concentration of toxin can more than double at each level of the food chain.
Which major evolutionary trends in green plants are supported by the order in which distinct plant taxa are found in the fossil record? A) The evolution of land plants from green algae, and the gradual evolution of traits that reduce the dependence of land plants on wet environments B) A distinct break from algae lineages and continued dependence on moisture for reproduction C) The steady development in the ability of land plants to produce increasingly sophisticated spores D) Nonvascular and vascular plants arising independently from separate taxa of green algae
A) The evolution of land plants from green algae, and the gradual evolution of traits that reduce the dependance of land plants on wet environments.
The global carbon cycle involves the movement of carbon among ecosystems. Which of the following is the largest reservoir of carbon? A) The ocean B) Human-induced changes C) Terrestrial ecosystems D) The atmosphere
A) The ocean
Why is the principle of parsimony important in constructing phylogenies? A) The principle of parsimony reduces the effect that homoplasy will have on the phylogenetic tree. B) The principle of parsimony allows researchers to use molecular data in constructing phylogenetic trees. C) The principle of parsimony is useful for constructing phylogenetic trees that include distantly related taxa. D) The principle of parsimony allows researchers to use morphologic data in constructing phylogenetic trees.
A) The principle of parsimony reduces the effect that homoplasy will have on the phylogenetic tree.
What is the logic behind the calculation of the net reproductive rate? A) The proportion of mothers alive multiplied by the average number of offspring for each age class summed to provide an estimate of population growth B) Total number of offspring summed over every age class C) Total numbers of mothers alive multiplied by the total number of offspring D) Age-specific fecundity is multiplied by the survivorship
A) The proportion of mothers alive multiplied by the average number of offspring for each age class summed to provide an estimate of population growth
Which is true of human impacts on the global water cycle? A) The water table is dropping on every continent. B) Use of water from rivers for irrigation effectively replenishes groundwater supplies by percolation. C) Asphalt and pavement increase the amount of groundwater by inhibiting evaporation. D) Croplands aid in water conservation due to their more extensive root systems compared to plants in natural habitats.
A) The water table is dropping on every continent.
Long-term studies of Beldingʹs ground squirrels show that immigrants move nearly 2 kilometers from where they are born and make up 1% to 8% of the males and 0.7% to 6% of the females in other populations. On an evolutionary scale, why is this significant? A) These immigrants provide a source of genetic diversity for the other populations. B) These immigrants are looking for less crowded conditions with more resources. C) Gradually, the populations of ground squirrels will move from a clumped to a uniform pattern of dispersion. D) Reproductive-age males tend to stay in their home population and are not driven out by other territorial males. E) These immigrants make up for the deaths of individuals, keeping the other populationsʹ size stable.
A) These immigrants provide a source of genetic diversity from the other populations
Which of the following biomes is correctly paired with the description of its climate? A) Tropical forests: nearly constant day length and temperature B) Tundra: long summers, mild winters C) Temperate grasslands: relatively warm winters, most rainfall in summer D) Temperate forest: relatively short growing season, mild winters E) Savanna: low temperature, uniform precipitation during the year
A) Tropical forests: nearly constant day length and temperature
Where in an angiosperm would a megasporangium be found? A) Within an ovule contained within an ovary of a flower B) Enclosed in the stigma of a flower C) Packed into pollen sacs within the anthers found on a stamen D) In the style of a flower
A) Within an ovule contained within an ovary of a flower.
Which of the following observations is not consistent with the hypothesis that increasing metazoan complexity is associated with an increase in the number of Hox loci? A) Within phyla, there is no correspondence between the number of Hox genes and complexity. B) Phyla that branch off early, such as sponges and cnidarians, have simple body plans with relatively few Hox loci. C) In vertebrates, the Hox clusters themselves appear to be duplicated several times. D) Hox loci are similar in structure and DNA sequence and are grouped in clusters. Hence, they are assumed to have arisen through duplication. When a new Hox gene appears within a lineage, most of the descendant taxa have a homologous Hox locus.
A) Within phyla, there is no correspondence between the number of Hox genes and complexity.
A genetic change that caused a certain Hox gene to be expressed along the tip of a vertebrate limb bud instead of farther back helped make possible the evolution of the tetrapod limb. This type of change is illustrative of __________. A) a change in a developmental gene or its regulation, which altered the spatial organization of body parts B) the influence of environment on development C) gene duplication
A) a change in a developmental gene or its regulation, which altered the spatial organization of body parts
The Hawaiian silversword originated from a species of tarweed, which is a plant native to present-day California. This plant colonized the Hawaiian islands approximately 5 million years ago, and currently consists of 30 species that are monophyletic, rapidly speciated, and have diversified ecologically into many different niches. This type of colonization is referred to as a/an ____________. A) adaptive radiation B) convergent evolution C) polytomy D) synapomorphy
A) adaptive radiation
Green algae differ from land plants in that many green algae __________. A) are unicellular B) chloroplasts contain the photosynthetic pigments chlorophyll a and b and the accessory pigment β-carotene C) cell walls, sperm, and peroxisomes are similar in structure and composition D) chloroplasts synthesize starch as a storage product
A) are unicellular
The energy invested in the production of new tissue by autotrophic organisms is __________. A) net primary productivity B) gross photosynthetic efficiency C) gross primary productivity D) maintenance
A) net primary productivity
Increasing the number of stomata per unit surface area of a leaf when atmospheric carbon dioxide levels decline is most analogous to a human __________. A) putting more red blood cells into circulation when atmospheric oxygen levels decline B) breathing more slowly as atmospheric oxygen levels increase C) removing red blood cells from circulation when atmospheric oxygen levels increase D) breathing faster as atmospheric carbon dioxide levels increase
A) putting more red blood cells into circulation when atmospheric oxygen levels decline.
The major role of detritivores in ecosystems is to __________. A) return energy lost to the ecosystem by other organisms B) recycle chemical nutrients to a form capable of being used by autotrophs C) provide an energy resource for autotrophs D) prevent the buildup of the organic remains of organisms and feces
B) recycle chemical nutrients to a form capable of being used by autotrophs
Approximately what percentage of solar radiation striking a plant is converted into chemical energy? A) 100 percent B) 1 percent C) 25 percent D) 10 percent E) 50 percent
B) 1 percent
Evidence indicates that plants increase the number of stomata in their leaves as atmospheric carbon dioxide (CO2) levels decline. Increasing the number of stomata per unit surface area would have the effect of doing which of the following? 1) Increasing dehydration of leaf tissues 2) Decreasing dehydration of leaf tissues 3) Countering the effect of declining CO2 on photosynthesis 4) Reinforcing the effect of declining CO2 on photosynthesis 5) Decreasing the oxygen (O2) content of air next to the leaves lower than it would otherwise be 6) Increasing the O2 content of air next to the leaves higher than it would otherwise be A) 2, 4, and 5 B) 1, 3, and 6 C) 2, 3, and 6 D) 1, 3, and 5
B) 1, 3, and 6
Which of the following assumptions have to be made regarding a mark-recapture estimate of population size? 1) Marked and unmarked individuals have the same probability of being trapped. 2) The marked individuals have thoroughly mixed with the population after being marked. 3) No individuals have entered or left the population by immigration or emigration. A) I and II B) I, II, and III C) I D) II and III E) II
B) 1,2,3
Which of the following statements regarding temperate grasslands are true? 1) Grassland soils are not very fertile. 2) Prairie fires can result from lightning strikes. 3) Grasslands are lower in productivity than tropical forest communities. 4) Grasslands have too little precipitation to support abundant tree growth. A) 2 and 4 B) 2, 3, and 4 C) 1 and 3 D) 1, 2, and 4 E) 1, 2, and 3
B) 2,3,4
In July 2008, the United States had a population of approximately 302 million people. How many Americans were there in July 2009, if the estimated 2008 growth rate was 0.88%? A) 303 million B) 304.6 million C) 5.5 million D) 2.7 billion E) 2.7 million
B) 304.6 million
Starting from a single individual, what is the size of a population of bacteria at the end of a two-hour time period if they reproduce by binary fission every 20 minutes? (Assume unlimited resources and no mortality.) A) 32 B) 64 C) 16 D) 8 E) 128
B) 64
t is estimated that snow geese will be able to sustain a rate of growth, r, of 0.088 indefinitely. If the flock currently contains 3,000 individuals, how long will it take to double in size? A) 264 years B) 7.9 years C) 34.1 years
B) 7.9 years
Based on current growth rates, Earth's total human population in 2050 will be closest to __________. A) 4 billion B) 8 billion C) 20 billion D) 2 million E) 3 billion
B) 8 billion
What is a phylogenetic tree? A) A picture of actual evolutionary relationships between species, based on our best guess B) A picture of probable evolutionary relationships between species, based on measured evidence C) A picture of probable evolutionary relationships between species, based on our best guess D) A picture of what actually happened in the evolutionary past
B) A picture of probable evolutionary relationships between species, based on measured evidence.
Which of the following possess stomata? A) Hepaticophyta B) Anthocerotophyta C) Ulvophyceae
B) Anthocerotophyta
Which lake zone would be absent in a very shallow lake? A) Pelagic zone B) Aphotic zone C) Limnetic zone D) Benthic zone E) Littoral zone
B) Aphotic zone
Why are natural lakes and ponds more common at higher latitudes? A) Because ice dams keep the water from leaving the body of water every winter B) Because the scouring action of past glaciers formed large depressions in the landscape C) Because beaver dams are more likely to be found at higher latitudes D) Because more precipitation falls at higher latitudes, resulting in more surface water
B) Because the scouring action of past glaciers formed large depressions in the landscape
Why is it obvious that tall corn plants seen from a car window do not belong to the bryophyte lineage? A) Bryophytes only grow in dry conditions. B) Bryophytes lack vascular tissue and grow close to the ground. C) Unlike corn, bryophytes do not carry out photosynthesis and would not appear green. D) Unlike corn and other crop plants, bryophytes do not reproduce sexually.
B) Bryophytes lack vascular tissue and grow close to the ground.
Which organisms would be found in the same trophic level? A) Pine trees and garden snakes B) Crickets and cows C) A plant and an herbivore D) A pack of wolves and a herd of deer
B) Crickets and Cows
Which factor is one that is used to calculate population growth? A) Marriage statistics B) Death rate C) Rates of food supply usage D) Rate of chronic illness
B) Death rate
Which of the following is a part of the natural nitrogen cycle? A) Plants take up atmospheric nitrogen through their stomata and convert it to organic forms. B) Decomposers convert detritus into ammonia. C) Animals take up nitrogen in the water they drink. D) When plants decompose, fungi absorb the nitrogen and remove it from the natural cycle.
B) Decomposers convert detritus into ammonia
Which of the following statements represents an important contrast between background extinctions and mass extinctions? A) Mass extinctions, such as the Cretaceous-Paleogene (K-Pg) event, tend to take out large-bodied organisms, whereas smaller organisms tend to be removed by background extinction. B) During mass extinctions, adaptations for survival and competition make little difference in the likelihood of extinction, whereas the opposite is true of background extinctions. C) Background extinctions are caused by rapid changes in the environment, whereas mass extinctions occur primarily in response to biological competition. D) Background extinctions occur only sporadically, whereas mass extinctions happen on a regular, periodic basis.
B) During mass extinctions, adaptations for survival and competition make little difference in the likelihood of extinction, whereas the opposite is true of background extinctions.
Pax-6 usually causes the production of a type of light-receptor pigment. In vertebrate eyes, though, a different gene (the rh gene family) is responsible for the light-receptor pigments of the retina. The rh gene, like Pax-6, is ancient. In the marine ragworm, for example, the rh gene causes production of c-opsin, which helps to regulate the worm's biological clock. Which of the following most likely accounts for vertebrate vision? A) Pax-6 was lost from the mammalian genome and was replaced by the rh gene much later. B) During vertebrate evolution, the rh gene for biological clock opsin was co-opted as a gene for light-receptor pigments. C) The Pax-6 gene mutated to become the rh gene among early mammals. D) In animals more ancient than ragworms, the rh gene(s) coded for light-receptor pigments; in lineages more recent than ragworms, the rh gene has flip-flopped several times between producing biological clock opsins and light-receptor pigments.
B) During vertebrate evolution, the rh gene for biological clock opsin was co-opted as a gene for light-receptor pigments.
Which of the following statements best describes why there is seasonality in climate? A) The sun is tilted on its axis, thus changing the amount of sunlight energy that reaches a specific place on the planet. B) Earth is tilted on its axis, thus changing the amount of sunlight energy received by a specific place on the planet during the year. C) Seasonality is driven by changes in the average monthly temperature. D) Mountains cause seasonality by blocking winds at certain times of the year.
B) Earth is tilted on its axis, thus changing the amount of sunlight energy received by a specific place on the planet during the year.
Which of the major taxa of land plants living today has only a single member? A) Cycads B) Ginkgos C) Gnetophytes D) Hornworts
B) Ginkgos
Which of the following groups is definitely monophyletic? A) Green algae B) Green plants C) Seedless vascular plants D) Nonvascular plants
B) Green plants
Which of the following key adaptations is found in many animals from the Burgess Shale fauna but is not found among fossils in the Doushantuo and Ediacaran faunas? A) Embryos B) Hard body parts C) Burrow formation D) Multicellularity
B) Hard body parts
Water at the source of a stream has which of the following characteristics? A) High nutrient levels B) High oxygen levels C) Slow movement D) High temperature
B) High oxygen levels
Which of the following statements about biogeochemical cycles is true? A) Nutrients remain in an animal until the animal's death. B) If a plant dies, the nutrients and the plant biomass become plant litter. C) Nutrients cannot move from one trophic level to a higher trophic level the way energy can. D) Nutrients are taken up directly from soil by animals and incorporated into their tissues.
B) If a plant dies, the nutrients and the plant biomass become plant litter.
Which of the following events might occur if the tilt of Earth's axis relative to its plane of orbit was increased to 33.5 degrees? A) In Australia, summer and winter would become less distinct seasons. B) In the United States, summers would become warmer and winters would become colder. C) Seasonal variation at the equator might decrease. D) The Northern Hemisphere and Southern Hemisphere would experience summer and winter at the same time.
B) In the United States, summers would become warmer and winters would become colder.
Which of the following statements describes an abiotic factor that may limit the geographic distribution of a species? A) Yucca moths lay their eggs only in the flowers of yucca plants and thus cannot live where yucca plants are absent. B) In warm winters, Carolina wrens are able to expand their range to northern states, but in cold winters, their range contracts to the south. C) In Africa, the range of domestic cattle is limited by the distribution of flies that transmit a fatal cattle disease. D) Male Townsend's warblers directly attack male hermit warblers.
B) In warm winters, Carolina wrens are able to expand their range to northern states, but in cold winters, their range contracts to the south.
Artificial selection has produced a distinct set of changes in wild forms of plants as they have been domesticated. Which of the following represents an example of domestication of crop plants by the process of artificial selection? A)Cross-pollination of the pepper plant in one backyard with the pepper plants in the neighboring yard B)Increase in kernel size in modern maize in comparison to teosinte, a wild grass C)Reduced protein content of cultivated plants such as corn D)Elimination of a field of cotton plants in an area undergoing drought
B) Increase in kernel size in modern maize in comparison to teosinte, a wild grass.
Experiments performed on the bridled goby in coral reefs and on song sparrows on Mandarte Island support the hypothesis that density-dependent effects can cause logistic population growth. What conclusions can be drawn from logistic growth models? A) Individuals survive better when the density is high, and clutch size increases as the density decreases. B) Individuals survive better and clutch size increases when the population density is low. C) Individuals survive better when the density is low, and clutch size increases when the density is high. D) Individuals survive better and clutch size increases when the density is high.
B) Individuals survive better and clutch size increases when the population density is low.
Which of the following statements about soil organic matter is true? A) If nutrients are converted to an inorganic form, they are no longer available for uptake by plants. B) Soil organic matter is rich in humic acids. C) Eventually, the nutrients in soil are converted from inorganic to organic matter, which is then available for uptake by plants. D) Soil is composed entirely of abiotic components.
B) Soil organic matter is rich in humic acids.
Which statement about the ecological services provided by plants best explains why coastal areas with cultivated fields and developed neighborhoods tend to suffer far more damage from hurricanes than do areas with natural forest and marsh habitats? A) Plants release oxygen into the environment. B) Intact forests and wetlands can reduce the effects of winds during a hurricane and lessen the impact of erosion. C) Intact forests and wetlands allow accumulated water to quickly run off a landscape. D) Developed habitats tend to be more humid than natural environments and are therefore more susceptible to the input of water during a hurricane.
B) Intact forests and wetlands can reduce the effects of winds during a hurricane and lessen the impact of erosion.
Which of the following statements is true of net primary productivity? A) There is no productivity in the depths of the oceans. B) Marine productivity is highest along coasts and in areas where water wells up from the ocean floor to the surface. C) Temperate areas are more productive than tropical areas. D) Deserts and arctic regions have the highest productivity.
B) Marine productivity is highest along coasts and in areas where water wells up from the ocean floor to the surface.
Why can metapopulations remain stable over time even if some subpopulations go extinct? A) Other subpopulations can exceed K, their carrying capacity, to make up for the localized extinctions. B) Migration from other subpopulations can reestablish formerly extinct subpopulations. C) Human fragmentation of large habitats into smaller, isolated habitats will create new habitats for the species. D) The species can re-evolve in the empty habitat patch from closely related species already present in the habitat.
B) Migration from other subpopulations can reestablish formerly extinct subpopulations.
Why are morphological innovations often associated with adaptive radiations? A) Morphological innovations often allow a species to replace competitors. B) Morphological innovations can open up new adaptive options that allow a species to exploit an underused resource. C) Morphological innovations disrupt natural selection, forcing species to find new adaptations. D) Morphological innovations prevent adaptive radiations most of the time.
B) Morphological innovations can open up new adaptive options that allow a species to exploit an underused resource.
How does NPP differ from GPP? A) NPP is dependent on climate, whereas GPP is an intrinsic attribute of the species producing energy. B) NPP is the amount of energy available for primary consumers, whereas GPP is the amount of energy produced by plants and other producers. C) NPP is the amount of productivity available for decomposers. D) NPP is the amount of energy available at each trophic level, whereas GPP is the sum of the productivity of all the NPPs.
B) NPP is the amount of energy available for primary consumers, whereas GPP is the amount of energy produced by plants and other producers.
Which of the following statements describes a situation that would be studied by a researcher interested in population ecology? A) Mutations in gill rakers affect the ability of individual salmon to absorb oxygen. B) Only a few salmon offspring return to the stream of their birth to breed. C) Sea lions and humans hunt salmon in streams. D) Decomposing salmon release nutrients that are used by other organisms in the stream.
B) Only a few salmon offspring return to the stream of their birth to breed.
Which of the following statements about freshwater environments is true? A) Lakes and ponds are divided into zones according to the depth of the water and the amount of oxygen available. B) Organisms that consume detritus are common in the benthic zones of lakes and ponds. C) Bogs are characterized by high water flow. D) Marshes and bogs are the most productive wetland habitats.
B) Organisms that consume detritus are common in benthic zones of lakes and ponds.
What adaptation reduced the dependence of seed plants on water for fertilization? A) Sporophytes B) Pollen grains C) Gametophytes D) Seed
B) Pollen grains
Which of the following is true about the components of ecosystems? A) Primary consumers are organisms that feed on dead organisms or their waste products. B) Primary producers are autotrophs or "self-feeders." C) All autotrophs use the sun's energy to produce chemical energy. D) Secondary consumers are in the second trophic level.
B) Primary producers are autotrophs or "self-feeders."
Morphological data supports a close relationship between whales and hippos, but DNA evidence contradicts this reconstruction. However, the distribution of SINEs helped researchers reconcile this apparent conflict. This is an example of __________. A) the difference between homology and analogy B) resolving scientific discrepancies with additional data C) the inability of science to resolve conflicts and identify truth D) the power of science
B) Resolving scientific discrepancies with additional data.
Which of the following is a genetic hypothesis proposed for the rapid diversification of body plans during the Cambrian period? A) New genes appeared in many different organisms through a mechanism that has not been identified. These are associated with new body plans. B) Several duplications of the homeotic genes that control major characteristics in body plans apparently arose about 540 million years ago, creating new body plans and appendage configurations. C) Reproductive isolation was nearly nonexistent; many "species" interbred to form hybrids that went on to become new species. D) Many mutations accumulated as a result of high exposure to UV radiation, creating many new kinds of organisms.
B) Several duplications of the homeotic genes that control major characteristics in body plans apparently arose about 540 million years ago, creating new body plans and appendage configurations.
Species with which life history traits are most likely to be endangered by human alterations? A) Species with low juvenile mortality rates, high adult mortality rates, and low fecundity B) Species with high juvenile mortality, low adult mortality, and low fecundity C) Species with high survivorship at all age classes and rates of population growth that are extremely sensitive to age-specific fecundity D) Species with low survivorship at all age classes and rates of population growth that are extremely sensitive to age-specific fecundity
B) Species with high juvenile mortality, low adult mortality, and low fecundity
In seed plants, which of the following is part of a pollen grain and has a function most like that of the seed coat? A) Stigma B) Sporopollenin C) Sporophyll D) Sporangium
B) Sporopollenin
The functions of the antheridia and archegonia make them synonymous to what organs in animals? A) Liver and kidneys B) Testes and ovaries C) Spleen and liver D) Lungs and heart
B) Testes and ovaries
Considering the current scientific literature on global warming, which statement best summarizes the most recent findings? A) The Intergovernmental Panel on Climate Change (IPCC) concluded that carbon dioxide is the sole cause of global warming. B) The Intergovernmental Panel on Climate Change (IPCC) concluded that the evidence for global warming is unequivocal and that it is very likely the result of human-induced changes in greenhouse gases. C) The Intergovernmental Panel on Climate Change (IPCC) concluded that current evidence suggests no link between human activity and climate change. D) The Intergovernmental Panel on Climate Change (IPCC) concluded that current evidence suggests that most of the warming over the past 50 years is attributable to human activities.
B) The Intergovernmental Panel on Climate Change (IPCC) concluded that the evidence for global warming is unequivocal and that it is very likely the result of human-induced changes in greenhouse gases.
Which variables are examples of the ecological life history of a species? A) The climate of where a species resides B) The age at which reproduction begins, the frequency of reproduction, and the number of offspring for each reproductive episode C) The altitude of where a species resides D) The largest size of an individual in a population
B) The age at which reproduction begins, the frequency of reproduction, and the number of offspring for each reproductive episode
Which of the following statements about exponential growth is true? A) Exponential growth does not add more individuals as N gets larger. B) The rate of growth, r, is an estimate of births subtracted by deaths. C) Exponential growth depends on carrying capacity. D) Exponential population growth will increase as the population reaches the carrying capacity.
B) The rate of growth, r, is an estimate of births subtracted by deaths.
Which of the following statements is true of monocots? A) The veins of their leaves form a netlike pattern. B) They are currently included in the phylum Anthophyta. C) Each possesses multiple cotyledons. D) They are in the clade that includes most human crops, except the cereal grains.
B) They are currently included in the phylum Anthophyta.
Suppose that the number of bird species is determined mainly by the amount of vertical heterogeneity found in the environment. If so, in which of the following biomes would the greatest number of bird species be found? A) Temperate grassland B) Tropical rain forest C) Temperate deciduous forest D) Savanna E) Desert
B) Tropical rain forest
Which survivorship curve applies to most plant species? A) Type I B) Type III C) Type II
B) Type III
A carp has a large number of offspring, but predators eat many of them during the first year of life. Once they survive to maturity, they have few predators. What type of survivorship curve does a carp have and why? A) Type II, because carp have a high survivorship initially that declines at the end of their life B) Type III, because carp have a low survivorship initially but a high survivorship once they have matured C) Type II, because carp have a steady survivorship throughout their life D) Type III, because carp have a steady survivorship
B) Type III, because carp have a low survivorship initially but a high survivorship once they have matured
Which action changes the abiotic components of an organism's environment? A) Introduction of exotic species B) Water sedimentation C) Interactions with offspring D) Extinction of predators
B) Water sedimentation
The gametophytes of Dawsonia mosses have an extensive system of rhizoids. Soil nitrogen is not solely absorbed by the rhizoids of these mosses because rhizoids __________. A) consist of single tubular cells or of filaments of cells B) are not absorptive structures C) are associated with fungi that inhibit mineral transfer from soil to rhizoids D) immediately transfer the nitrogen to the sporophyte
B) are not absorptive structures.
If you study the interactions between cheetahs and the Thomson's gazelles they prey upon, you would primarily be doing __________ ecology. A) population B) community C) organismal D) ecosystem
B) community
A population is a __________. A) vast region that has a combination of plant and animal species living in a distinct climate B) group of individuals from the same species that live in the same area at the same time C) group of individuals from different species that live in the same area at the same time D) group of individuals that are able to interbreed and produce viable offspring
B) group of individuals from the same species that live in the same area at the same time
The carnivorous pitcher plant is successful in bog habitats because it __________. A) can tolerate the lack of oxygen in the bog water B) has an extra source of nitrogen, which gives it a competitive advantage C) can tolerate the high acidity of the bog water D) can gain oxygen in an unusual way
B) has an extra source of nitrogen, which gives it a competitive advantage
In some European countries, the population is declining. In these countries, the net reproductive rate, R0, is __________. A) impossible to predict B) less than 1 C) greater than 1 D) equal to 1
B) less than 1
The evolution of animal species has been prolific (the estimates go into the millions and tens of millions). Much of this diversity is a result of the evolution of novel ways to __________. A) form an embryo and establish a basic body plan B) sense, feed, and move C) reproduce D) arrange cells into tissues
B) sense, feed, and move
The structural integrity of bacteria is to peptidoglycan, as the structural integrity of plant spores is to __________. A) lignin B) sporopollenin C) secondary compounds D) cellulose
B) sporopollenin
The Cambrian explosion was significant in the history of life because __________. A) plant and animal fossils were found together for the first time B) there was an explosion in ecological diversity among animals C) good fossils from this period are available to study D) there was an explosion in animal abundance
B) there was an explosion in ecological diversity among animals
Photosynthetic organisms __________. A) use chemical energy to synthesize organic compounds B) use light energy to synthesize organic compounds from inorganic compounds C) convert light energy into matter D) synthesize inorganic compounds from organic compounds
B) use light energy to synthesize organic compounds from inorganic compounds
If plants in a northern temperate area use 26,400 kcal/m2 (kilocalories per square meter) of energy from solar radiation in photosynthesis, and the total amount of solar radiation energy reaching that area is 2,640,000 kcal/m2, what is the overall gross photosynthetic efficiency (the percentage of total solar energy captured by plants)? A) 100 percent B) 0.1 percent C) 1 percent D) 0.01 percent
C) 1 percent
In 2008, the population of New Zealand was approximately 4,275,000 people. If the birth rate was 14 births for every 1,000 people, approximately how many births occurred in New Zealand in 2008? A) 600,000 B) 6,000 C) 60,000 D) 140,000 E) 42,275
C) 60,000
What is the estimated population size from these mark-recapture data? Three hundred animals were originally captured and marked, and 200 were captured the second time, with 100 of them being marked. A) 400 B) 500 C) 600 D) 300
C) 600
Charles Darwin's finches, collected from the Galápagos Islands, illustrate which of the following? A) Vestigial anatomical structures B) Mutation frequency C) Adaptive radiation D) Ancestors from different regions E) The accuracy of the fossil record
C) Adaptive radiation
Cheatgrass has been able to invade dry, temperate grasslands and the arid, shrub-dominated habitats (sage-steppe) of North America. Which of the following are reasons for this? 1) Cheatgrass is an annual, so there are seeds in the ground ready to grow any year. 2) Cheatgrass is somewhat fire-tolerant. 3) Cheatgrass promotes fire frequency and increases fire intensity. 4) Cheatgrass competes successfully with bunchgrasses for water and nutrients. A) 2 and 4 B) 1, 2, and 4 C) All of the listed answers (1, 2, 3, and 4) are reasons for this. D) 1 and 3 E) 2,3,4
C) All of the above
In which terrestrial area is global warming most likely to allow coniferous trees to encroach? A) Boreal forests B) Tropical wet forests C) Arctic tundra D) Temperate forests
C) Arctic tundra
The state of Hawaii is made of eight large islands and over a hundred smaller islands. The island of Hawaii is the most southeastern of the eight largest islands and is also closest to the seafloor spreading center from which the Pacific plate originates, about 5,600 km farther to the southeast. Assuming equal sedimentation rates for the entire region, what should be the location of the thickest sediment layer, and thus the area with the greatest diversity of fossils above the oceanic crust? A) Where the islands are most concentrated (highest number of islands per unit surface area) B) Between the island of Hawaii and the seafloor spreading center C) Around the base of Kauai, the oldest of the large Hawaiian islands D) Around the base of the island of Hawaii, the most recently formed Hawaiian island
C) Around the base of Kauai, the oldest of the large Hawaiian islands
Which of the following statements best represents current thinking about the rise of mammals after the K-Pg extinction? A) Mammals were inherently better competitors than the dinosaurs; the K-Pg impact simply sped up the replacement, which was already well under way. B) Both mammals and dinosaurs survived the asteroid, but the mammals were much better adapted to the new environments created by the impact and therefore underwent adaptive radiation. C) By chance, the K-Pg impact caused extinction of the dinosaurs but did not greatly affect the small, nocturnal, scavenging mammals. The release from competition allowed the mammals to diversify. D) Mammalian diversity increased dramatically prior to the impact, but the population sizes of every species remained small until after the dinosaurs were extinct.
C) By chance, the K-Pg impact caused extinction of the dinosaurs but did not greatly affect the small, nocturnal, scavenging mammals. The release from competition allowed the mammals to diversify.
Identify the correct pollination association. A) Bee-pollinated flowers have long, tubelike structures to protect the bees. B) Brightly colored flowers are pollinated by moths, which are attracted to bright colors. C) Carrion flowers produce molecules that smell like rotting flesh to attract flies. D) Flowers pollinated by hummingbirds are generally white because hummingbirds lack color vision.
C) Carrion flowers produce molecules that smell like rotting flesh to attract flies.
Which of the following is not a limitation of the fossil record? A) Habitat bias B) Abundance bias C) Cladistic bias D) Taxonomic and tissue bias E) Temporal bias
C) Cladistic bias
Which of the following types of organisms is likely to have the widest geographic distribution? A) Lizards B) Bears C) Songbirds D) Deer E) Bacteria
E) Bacteria
Which of the following have been presented as a cause for sudden irreversible shifts, such as those seen in a forested area converting to a grassland? A) Climate change and forest fires B) Invasive species C) Climate change, forest fires, and invasive grasses D) Climate change E) Forest fires
C) Climate change, forest fires, and invasive grasses
What is the main difference between climate and weather? A) Climate describes shorter-term conditions than weather. B) Weather describes a larger area than climate. C) Climate describes longer-term conditions than weather. D) Climate is primarily a term used by ecologists; weather is primarily a term used by the general public. E) Weather includes temperature, and climate does not.
C) Climate describes longer-term conditions than weather.
Which of the following terms describes an arrangement of a school of fish? A) Random B) Uniform C) Clumped D) Abiotic
C) Clumped
Which of the following causes populations to better exhibit a logistic population growth model rather than an exponential growth model? A) Decreased death rate B) Favorable climatic conditions C) Competition for resources D) Removal of predators
C) Competition for resources
In the study of Anolis lizards that colonized various Caribbean islands, similar habitats and ecological types were found on Hispaniola and Jamaica. What observations suggest that adaptive radiations occur in response to habitat availability and the absence of competitors? A) Each island was colonized by a different species initially, and that species underwent a radiation, giving rise to new species that occupied different habitat types. There was no similarity, however, in the adaptations from one island to another. The phylogeny for each island was completely unique and totally unlike that of any other island. B) Each island was initially colonized by a different species that occupied its preferred habitat. Subsequent colonizing species were successful only if they could use an unoccupied habitat type. The phylogeny for each island was the same throughout the region because no evolution occurred, only colonization. C) Different islands were initially colonized by species that differed in habitat preference, but in both cases subsequent speciation produced a range of ecological specialists occupying similar habitat niches. The phylogeny for each island was unique, but species evolved having similar sets of adaptations for each habitat. D) The first colonists on every island were always the same species, a twig-dwelling specialist. However, in every case, that species gave rise to the same set of other species that specialized in different habitats. The phylogeny for each island had the same root and the same pattern of speciation.
C) Different islands were initially colonized by species that differed in habitat preference, but in both cases subsequent speciation produced a range of ecological specialists occupying similar habitat niches. The phylogeny for each island was unique, but species evolved having similar sets of adaptations for each habitat.
Which of the following choices directly causes change in all of the others? A) Evaporation of water from ocean surfaces B) Ocean currents C) Differential heating of Earth's surface D) Global wind patterns
C) Differential heating of the Earth's surface
Which of the following organisms likely has the most Hox genes? A) Bees B) Jellyfish C) Dolphins D) Slugs
C) Dolphins
Which statement most accurately describes how nutrients and energy are used in ecosystems? A) Nutrients flow through ecosystems; energy cycles within ecosystems. B) Energy can be converted into nutrients; nutrients cannot be converted into energy. C) Energy flows through ecosystems; nutrients cycle within and through ecosystems. D) Nutrients are used in ecosystems; energy is not. E) Nutrients can be converted into energy; energy cannot be converted into nutrients.
C) Energy flows through ecosystems; nutrients cycle within and through ecosystems.
Which region on Earth receives the most solar radiation per unit area over a year? A) North Pole B) 30 degrees north and 30 degrees south latitude C) Equator D) South Pole
C) Equator
Which of the following environmental challenges has so far not shown a slowdown, partial recovery, or significant recovery? A) Phosphate pollution B) Acid rain C) Global warming D) Ozone hole
C) Global warming
Which of the following statements regarding turnover in a lake is correct? A) The surface water gets to 4°C only by cooling. B) Fall turnovers and spring turnovers are exactly the same. C) In a fall turnover, water cools to 4°C and sinks, which disturbs sediments in the benthic zone. D) In a fall turnover, dense water at 4°C rises and disturbs sediments in the benthic zone.
C) In a fall turnover, water cools to 4 C and sinks, which disturbs sediments in the benthic zone.
What is the trade-off between life expectancy and fecundity? A) Birds that lay many eggs tend to survive longer. B) Longer-lived individuals tend to have more offspring. C) Investing more resources in reproduction means there are fewer resources available for survival. D) Investing in reproduction leads to a longer life.
C) Investing more resources in reproduction means there are fewer resources available for survival.
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 various populations are stimulated to a higher reproductive potential B) Old growth, because each of the species is well established and can produce many offspring C) Logged, because the disturbed forest affords more resources for increased specific populations to grow D) Exponential growth is equally probable in old-growth and logged forests E) Old growth, because of stable conditions that would favor exponential growth of all species in the forest
C) Logged, because the disturbed forest affords more resources for increased specific populations to grow
Which of the following statements is true about the metapopulation model? A) The overall number of individuals in a metapopulation undergoes major fluctuations. B) For long-term survival of the metapopulation, the subpopulations need to learn to live in corridors of the habitat. C) Migration from nearby populations can reestablish populations. D) When subpopulations blink on and off over time, they typically threaten the entire metapopulation.
C) Migration from nearby populations can reestablish populations.
What ecosystem service is provided by land plants? A) Plants contribute CO2 to the environment. B) Plants are the dominant primary consumers in terrestrial ecosystems. C) Plants perform oxygenic photosynthesis. D) Plants are key secondary consumers in terrestrial ecosystems.
C) Plants perform oxygenic photosynthesis.
A cow's herbivorous diet indicates that it is a(n) __________. A) autotroph B) producer C) primary consumer D) secondary consumer E) decomposer
C) Primary consumer
Virtually all of the adaptations that allow plants to occupy dry, terrestrial habitats are present, including water-conducting tissue and roots. These characteristics of plants were most noted in what major interval of plant origination? A)Diversification of angiosperms B) Diversification of gymnosperms C) Silurian-Devonian Explosion D) Carboniferous period
C) Silurian-Devonian Explosion
In which community would organisms most likely have adaptations enabling them to respond to seasonal variations of sunlight? A) Tropical rain forest B) Savanna C) Temperate forest D) Coral reef E) Deep ocean
C) Temperate forest
Over the past decade, which of the following has occurred? A) As predicted by global warming, terrestrial NPP has increased with the warmer temperatures. B) Terrestrial NPP in the Sahara has increased. C) Terrestrial NPP has decreased in some parts of the world but increased in others. D) NPP has increased in terrestrial environments.
C) Terrestrial NPP has decreased in some parts of the world but increased in others.
All animals with eyes or eyespots that have been studied so far share a gene in common. When mutated, the gene Pax-6 causes the lack of eyes in fruit flies, tiny eyes in mice, and missing irises (and other eye parts) in humans. The sequence of Pax-6 in humans and mice is identical. There are so few sequence differences with fruit fly Pax-6 that the human/mouse version can cause eye formation in eyeless fruit flies, even though vertebrates and invertebrates last shared a common ancestor more than 500 million years ago. The appearance of Pax-6 in all animals with eyes can be explained in multiple ways. Based on the information above, which explanation is most likely? A) The Pax-6 gene is really not one gene. It is many different genes that, over evolutionary time and due to convergence, have come to have a similar nucleotide sequence and function. B) The need for eyes has resulted in the separate evolution of Pax-6 genes. C) The Pax-6 gene was an innovation of an ancestral animal of the early Cambrian period. Animals with eyes or eyespots are descendants of this ancestor. D) Pax-6 in all of these animals is not homologous; it arose independently in many different animal phyla due to intense selective pressure favoring vision.
C) The Pax-6 gene was an innovation of an ancestral animal of the early Cambrian period. Animals with eyes or eyespots are descendants of this ancestor.
Which of the following is an indicator of net primary productivity (NPP)? A) The average yearly temperature in a region B) The amount of sunlight a biome receives C) The aboveground plant biomass D) The ability of an exotic species to become invasive
C) The aboveground plant biomass
Which of the following is an abiotic component of a burrow community? A) The food sources in the burrow B) The abundance of each species in the burrow C) The air quality of the burrow D) The different species living in the burrow
C) The air quality of the burrow
What happens when N is equal to K? A) The growth rate speeds up. B) The population is at 0. C) The growth rate of the population is 0. D) The growth rate begins to slow.
C) The growth rate of the population is 0.
Why are the spring and fall lake turnovers important for aquatic ecosystems? A) Lake turnovers force normally bottom-dwelling species to the surface for twice-yearly production of vitamin D. B) Lake turnovers bring oxygen-rich water from the lake bottom up to the lake surface. C) The turnovers bring nutrient-rich water from the bottom of the lake up to the top of the lake. D) Lake turnovers allow the melting of winter ice.
C) The turnovers bring nutrient-rich water from the bottom of the lake up to the top of the lake.
Biologists hypothesize that the first land plants had a low, sprawling growth habitat. Which of the following statements supports this hypothesis? A) Low, sprawling growth protected the first land plants from herbivores. B) The low, sprawling growth increased the surface area of the first land plants, providing them with additional light for photosynthesis. C) To obtain water, the first land plants had to keep their tissues in direct contact with moist soil. D) The wind speed was much greater at that time than it is now, restricting the height of the first land plants.
C) To obtain water, the first land plants had to keep their tissues in direct contact with moist soil.
Under what condition might r, the per capita rate of increase, approach rmax, the intrinsic rate of increase? A) When females delay reproduction to a later age class B) When fecundity decreases C) When resources are abundant D) When death rates increase due to disease
C) When resources are abundant
Which pair of morphological traits is used to define the three categories into which land plants are classified? A)Which habitats the plants colonize, and which photosynthetic pigments they contain B)Whether or not the plants produce flowers, and whether or not their seeds are developed in enclosed structures C)Whether or not the plants contain vascular tissue, and whether or not they produce seeds D)Where plants appear in the fossil record, and the closeness of their phylogenetic relationships
C) Whether or not the plants contain vascular tissue, and whether or not they produce seeds
Which of the following organisms is incorrectly paired with its trophic level? A) Fungus—detritivore B) Cyanobacterium—primary producer C) Zooplankton—primary producer D) Grasshopper—primary consumer
C) Zooplankton- primary producer
A fruit is most commonly __________. A) a thickened style B) an enlarged ovule C) a mature ovary D) a modified root
C) a mature ovary
The Permian period ended, and then rapid speciation occurred as new animal and plant forms evolved. The most likely explanation for this is __________. I) adaptive radiation II) ecological opportunity III) lack of competition IV) morphological innovation A) two of the listed answers B) none of the listed answers (I, II, III, or IV) C) all of the listed answers (I, II, III, and IV) D) just one of the listed answers E) three of the listed answers
C) all of the listed answers (I,II,III and IV)
In each fly species, the entire body segment that gave rise to the original flight wings is missing. The mutation(s) that led to the flightless condition could have __________. A) duplicated all of the Hox genes in these flies' genomes B) originated in another species C) altered the expression of a Hox gene
C) altered the expression of a Hox gene
Fire suppression by humans __________. A) is a management goal of conservation biologists to maintain the healthy condition of forest communities B) will always result in an increase in species diversity in a given biome C) can change the species composition within biological communities D) is necessary for the protection of threatened and endangered forest species E) will ultimately result in sustainable production of increased amounts of forest products for human use
C) can change the species composition within biological communities.
Different aquatic biomes are distinguished by __________. A) the number and type of animal species that occur there B) precipitation and availability of light C) depth of water and rate of water movement D) rate of water movement and temperature
C) depth of water and rate of water movement
Generally speaking, deserts are located in places where air masses are usually __________. A) humid B) rising C) descending D) expanding E) tropical
C) descending
Fruit fly eyes are the compound type, which is structurally very different from the camera-type eyes of mammals. Even the camera-type eyes of mollusks, such as octopi, are structurally quite different from those of mammals. Yet fruit flies, octopi, and mammals possess very similar versions of Pax-6. The fact that the same gene helps produce very different types of eyes is most likely caused by __________. A) the independent evolution of this gene at many different times during animal history B) variations in the number of Pax-6 genes among these organisms C) differences in the control of Pax-6 expression among these organisms D) the few differences in nucleotide sequence among the Pax-6 genes of these organisms
C) differences in the control of Pax-6 expression among these organisms
If an organism has a relatively large number of Hox genes in its genome, it most likely __________. A) has multiple paired appendages along the length of its body B) has Hox genes expressed in all cells of its body C) has a relatively complex anatomy D) belongs to one of the first groups to evolve on Earth
C) has a relatively complex anatomy
Stamens, sepals, petals, carpels, and pine cone scales are all __________. A) capable of photosynthesis B) female reproductive parts C) modified leaves D) found on angiosperms
C) modified leaves
Populations that are likely to persist typically ____________. A) have low genetic diversity B) are of small size C) occupy larger geographic regions D) are isolated from other populations
C) occupy larger geographic regions
The duplication of homeotic (Hox) genes has been significant in the evolution of animals because it __________. A) caused the extinction of major groups B) allowed animals to survive on significantly fewer calories C) permitted the evolution of novel forms D) reduced morphological diversity into simpler forms of life
C) permitted the evolution of novel forms
Which of the following variables should be used to estimate population growth in a continuously growing population? A) λ B) N C) r D) Δ
C) r
Which of the following is a constant for a given species? A) N, the population size B) r, the per capita rate of increase C) rmax, the intrinsic rate of increase D) K, the carrying capacity
C) rmax, the intrinsic rate of increase
The main cause of the increase in the amount of carbon dioxide in Earth's atmosphere over the past 150 years is __________. A) increased worldwide standing crops B) increased worldwide primary production C) the burning of larger amounts of wood and fossil fuels D) additional respiration by the rapidly growing human population
C) the burning of larger amounts of wood and fossil fuels
When do lake turnovers occur? A) In the winter and summer B) In response to biotic factors C) When water at the top of the lake becomes denser than the water below D) When the organisms in deep, oxygen-poor regions signal for more oxygen
C) when water at the top of the lake becomes denser than the water below
Which statements about dispersal are correct? 1) Dispersal is a common component of the life cycles of plants and animals. 2) Colonization of devastated areas after floods or volcanic eruptions primarily depends upon climate. 3) Seeds are important dispersal stages in the life cycles of most flowering plants. 4) Dispersal occurs only on an evolutionary time scale A) 2, 3, and 4 B) 1, 2, and 4 C) 2 and 4 D) 1 and 3 E) 1, 2, and 3
D) 1 and 3
Which zone is found only in freshwater environments? A) Aphotic zone B) Benthic zone C) Neritic zone D) Littoral zone
D) Littoral zone
What factor might cause 10-year cycles in populations? A) Climate change B) A consistently low level of resources C) A consistently high population of predators D) A population of predators follows the prey and exhibits a similar cycle.
D) A population of predators follows the prey and exhibits a similar cycle.
Which of the following is an example of an ecosystem? A) The plants and fish in an aquarium B) All of the species of trout in a 500-square-hectare river drainage system C) The plants, animals, and decomposers that inhabit an alpine meadow D) A tropical rain forest
D) A tropical rain forest
Which population would be most likely to experience exponential growth? A) A population with a large number of individuals B) A population living in a habitat with limited resources C) A population living in a habitat with a low carrying capacity D) A young population with few individuals
D) A young population with a few individuals
Which of the following statements is not true? A) The nonvascular plants form a monophyletic group. B) Green algae in the lineage Charophyceae are the closest living relatives of land plants. C) Horsetails and ferns form a distinct lineage. They have vascular tissue but reproduce via spores, not seeds. D) According to the fossil record and phylogenetic analyses, angiosperms evolved before gymnosperms; angiosperms are the only land plants with vessels.
D) According to the fossil record and phylogenetic analyses, angiosperms evolved before gymnosperms; angiosperms are the only land plants with vessels.
Which of the following statements is not true? A) The nonvascular plants form a monophyletic group. B) Green algae in the lineage Charophyceae are the closest living relatives of land plants. C) Horsetails and ferns form a distinct lineage. They have vascular tissue but reproduce via spores, not seeds. D) According to the fossil record and phylogenetic analyses, angiosperms evolved before gymnosperms; angiosperms are the only land plants with vessels.
D) According to the fossil record and phylogenic analyses, angiosperms evolved before gymnosperms; angiosperms are the only land plants with vessels.
Which of the following events did not take place during the biotic recovery from the K-Pg extinctions? A) Many woody and flowering plant species were lost in the K-Pg event and were replaced by a radiation of fern species. B) Mammals survived and radiated after the K-Pg event; all major orders appeared within 5 million to 10 million years, replacing dinosaurs and marine reptiles. C) Many marine invertebrates, such as clams and snails, were greatly reduced in diversity by the K-Pg event; new species took 4 million 8 million years to evolve and replace the extinct species. D) All large-bodied reptiles died out in the extinction and were replaced by smaller-bodied species of dinosaurs and crocodiles.
D) All large-bodied reptiles died out in the extinction and were replaced by smaller-bodied species of dinosaurs and crocodiles.
Which of the following events has been associated with the extinction of the dinosaurs at the end of the Cretaceous 65 million years ago? A) An outbreak of a highly pathogenic virus occurred; mammals were apparently immune, but reptiles had no defense against it. B) An outbreak of global volcanic activity occurred that both directly, through eruption of magma, and indirectly, through ash clouds blocking the sun, caused massive mortality in plants and animals. C) A worldwide change in climate caused by increased carbon dioxide in the atmosphere led to melting of the ice caps and dramatic changes in sea level. D) An asteroid impact caused fires, acid rain, and a massive dust cloud that blocked sunlight for some time, causing rapid global cooling and low plant productivity.
D) An asteroid impact caused fires, acid rain, and a massive dust cloud that blocked sunlight for some time, causing rapid global cooling and low plant productivity.
Which of these ecosystems has the lowest net primary production per square meter? A) A grassland B) A salt marsh C) A coral reef D) An open ocean E) A tropical rain forest
D) An open ocean
Seed plants are a monophyletic group consisting of what two groups? A) Erythrocytes and leukocytes B) Rhizoids and lichens C) Green algae and liverworts D) Angiosperms and gymnosperms
D) Angiosperms and Gymnosperms
What happens to animal and plant diversity as latitude decreases toward the equator? A) Animal and plant diversity are not affected by latitudinal changes. B) Animal and plant diversity decrease in variation per unit area. C) Animal and plant diversity decrease. D) Animal and plant diversity increase. E) Animal and plant diversity increase in variation per unit area.
D) Animal and plant diversity increase.
Why are changes in the global carbon cycle important? A) Less atmospheric carbon means that there are fewer fossil fuels available. B) More atmospheric carbon dioxide means that there is less carbon available for the growth of terrestrial plants. C) The global carbon cycle is the only factor affecting Earth's climate. D) Carbon dioxide is a greenhouse gas
D) Carbon dioxide is a greenhouse gas
Which of the following is most likely to contribute to density-dependent regulation of populations? A) Fires B) Earthquakes C) The removal of toxic waste by decomposers D) Competition for nutrients E) Floods
D) Competition for nutrients.
A population of frogs in North America breeds in the spring and estivates (is dormant) every winter. Which type of population growth is this? A) Facultative growth B) Indeterminate growth C) Continuous growth D) Discrete growth
D) Discrete growth
Which of the following statements best supports the hypothesis that flowers are adaptations increasing fertilization success in terrestrial environments? A) Flowers are adaptive because they produce endosperm, which protects the female gametophyte from predators. B) Heterospory, the production of two distinct types of spores by different structures, is unique to flowers. C) The evolution of the flower increased the success of wind pollination. D) Flowers attract pollinators to increase pollination success.
D) Flowers attract pollinators to increase pollination success.
Which group of seed plants is named for producing seeds that are not enclosed in an ovary, where the majority of species also exhibit unique, cone-shaped reproductive structures? A)Cycads B)Gnetophytes C)Angiosperms D)Gymnosperms
D) Gymnosperms
What is the primary determinant of future human population size estimates? A) The number of predators B) The amount of space on Earth C) The amount of food present on Earth D) How many children each woman decides to have
D) How many children each woman decides to have
Which of the following is an example of ecosystem studies? A) Study of behavioral interactions of predators and prey B) Changes in the abundance of a species over time C) How species interact within the ecosystem D) How the energy in sunlight dissipates as it flows through an ecosystem
D) How the energy in sunlight dissipates as it flows through an ecosystem.
Humans have substantially altered the global nitrogen cycle over the past century. How? A) Global warming has reduced the conversion of nitrogen gas to ammonium and other ionic forms. B) Humans have dramatically increased nitrogen availability as a side effect of internal engine fuel combustion. C) The number of gigatons of nitrogen produced has declined in recent years. D) Humans are responsible for almost doubling the amount of nitrogen available by natural means.
D) Humans are responsible for almost doubling the amount of nitrogen available by natural means.
White-tailed deer were quite rare across the northeastern United States approximately 100 years ago, but now their populations are generally considered to be too high. What do you predict has caused this? A) Deer hunting was discouraged, and deer from other areas in the United States moved into the unoccupied habitat. B) Due to the population scarcity, diseases that attack deer were eliminated. C) Deer prefer habitat that is not affected by people. D) Hunting females was prevented, and the intrinsic fecundity rate is actually quite high.
D) Hunting females was prevented, and the intrinsic fecundity rate is actually quite high.
Global warming, as demonstrated by observations such as the rise in average ambient temperatures and the melting of glaciers, has already had many effects on living organisms. Which of the following might best offer a solution to this problem? A) Increase the ability of animals to migrate to more suitable habitats. B) Continue to measure these and other parameters of the problem. C) Recycle as much as possible. D) Limit the burning of fossil fuels and the loss of forested areas. E) Do nothing; nature will attain its own balance
D) Limit the burning of fossil fuels and the loss of forested areas.
Which of the following studies would shed the most light on the impacts of climate change on the future distribution of organisms in temperate regions? A) There is no scientific study that can help make predictions on the future distribution of organisms. B) Quantify the impact of human activities on present-day populations of threatened and endangered species to assess the rate of extirpation and extinction. C) Remove, to the mineral soil, all of the organisms from an experimental plot, and monitor the colonization of the area over time in terms of both species diversity and abundance. D) Look at the climatic changes that occurred since the last ice age and how species redistributed as glaciers melted; then make predictions on future distribution in species based on past trends. E) Compare and contrast the flora and fauna of warm/cold/dry/wet climates to shed light on how they evolved to be suited to their present-day environment.
D) Look at the climatic changes that occurred since the last ice age and how species redistributed as glaciers melted; then make predictions on future distribution in species based on past trends.
In ecosystems, why is the term cycling used to describe material transfer, whereas the term flow is used for energy exchange? A) Both material and energy flow in a never-ending stream within an ecosystem. B) Both material and energy are recycled, and are then transferred to other ecosystems, as in a flow. C) Materials are cycled into ecosystems from other ecosystems, but energy constantly flows within each ecosystem. D) Materials are repeatedly used, but energy flows through and out of ecosystems.
D) Materials are repeatedly used, but energy flows through and out of ecosystems.
A sporophyte produces spores by which process? A) Diffusion B) Sporophylium C) Mitosis D) Meiosis
D) Meiosis
A sporophyte produces spores by which process? A) Diffusion B) Mitosis C) Sporophylium D) Meiosis
D) Meiosis
The importance of computers and of computer software to modern cladistics is most closely linked to advances in __________. A) radiometric dating B) light microscopy C) Linnaean classification D) molecular genetics E) fossil discovery techniques
D) Molecular genetics
Why would gene duplication events, such as those seen in the Hox gene complex, set the stage for adaptive radiation? A) There are more copies of genes, meaning speciation has occurred by polyploidy. B) The original gene copy is the outgroup, and the new gene copies are the adaptive radiation. C) Without duplicated genes, species would be vulnerable to extinction. D) One copy of a gene can perform the original function, while other copies are available to take on new functions.
D) One copy of a gene can perform the original function, while other copies are available to take on new functions.
Which of the following flower parts develops into a seed? A) Carpel B) Stamen C) Ovary D) Ovule
D) Ovule
What is the top down hypothesis? A) Populations are controlled by parental influence. B) Populations are controlled by random factors. C) Populations are controlled mostly by resource availability. D) Populations are controlled mostly by predators.
D) Populations are controlled mostly by predators.
Which of the following characteristics helped seedless vascular plants better adapt to life on land? A) Photosystem II B) A dominant gametophyte C) An unbranched sporophyte D) Stomata on leaves
D) Stomata on leaves.
After sunlight, which would be the next most important factors for growth of terrestrial plants? A) Temperature and wind B) Wind and fire C) Moisture and wind D) Temperature and moisture
D) Temperature and moisture
What are the implications of the fact that the hare population increases most when food is high and predators are excluded? A) The lynx population is controlled by the hare population. B) The hare population is controlled entirely by the lynx population. C) The hare population is controlled entirely by food supply. D) The hare population is controlled by both food supply and the lynx population.
D) The hare population is controlled by both food supply and the lynx population
The proportion of offspring that survive to a particular age is known as ___________. A) net reproductive rate B) survival C) fecundity D) survivorship
D) survivorship
Air masses formed over the Pacific Ocean are moved by prevailing westerly winds, and they encounter extensive north-south mountain ranges, such as the Sierra Nevadas and the Cascades. Which statement best describes the outcome of this encounter between a landform and an air mass? A) The cool, dry Pacific air heats up and picks up moisture from evaporation of the snowcapped peaks of the mountain range, releasing this moisture as precipitation when the air cools while descending on the leeward side of the range. B) These air masses remain essentially unchanged in moisture content and temperature as they pass over the mountain ranges. C) These air masses are blocked by the mountain ranges, producing high annual amounts of precipitation on the windward sides of the mountain ranges. D) The warm, moist Pacific air rises and cools, releasing precipitation as it moves up the windward side of the range. This cool, now-dry air mass descends on the leeward side of the range. E) The cool, moist Pacific air heats up as it rises, releasing precipitation as it passes the tops of the mountains. This warm, now-dry air cools as it descends on the leeward side of the range.
D) The warm, moist Pacific air rises and cools, releasing precipitation as it moves up the windward side of the range.
Green algae and land plants have been hypothesized to possess similar traits. Which of the following statements is not true? A) Their chloroplasts contain photosynthetic pigments chlorophyll a and b. B) They have similar arrangements of the internal thylakoids. C) Their chloroplasts synthesize starch as a storage product. D) Their cell walls, ovaries, and perizonum are similar in structure and composition.
D) Their cell walls, ovaries, and perizonum are similar in structure and composition.
Which of the following statements is true of monocots? A) Each possesses multiple cotyledons. B) They are in the clade that includes most human crops, except the cereal grains. C) The veins of their leaves form a netlike pattern. D) They are currently included in the phylum Anthophyta.
D) They are currently included in the phylum Anthophyta
Why was the evolution of lignin-reinforced cell walls significant? A) They were a primary, or major deterrent to predators. B)The lignin-reinforced cell made it possible for nonvascular plants to display their transporting systems above ground. C) They ensured that plants would be able to remain intact to fight pollinators. D) They provided the support plants needed to grow upright and not fall over in response to wind or gravity. This erectness allowed plants to compete for sunlight.
D) They provided the support plants needed to grow upright and not fall over in response to wind or gravity. This erectness allowed plants to compete for sunlight.
Which of the statements is true regarding Ulvophyceae? A) They are important consumers in the seas. B) They are mostly multicellular. C) They are paraphyletic. D) They reproduce asexually and sexually.
D) They reproduce asexually and sexually.
Which of the following statements is an accurate description of tracheids? A) Tracheids are found only in the most recent taxa of vascular plants. B) Tracheids transport water through gaps in their primary cell walls. C) The ability of tracheids to provide support comes from their cellulose-based primary cell wall. D) Tracheids are water-conducting cells found in all vascular plants.
D) Tracheids are water-conducting cells found in all vascular plants.
Major human impacts on ecosystems include farming, logging, and burning. These processes all result in accelerated nutrient export by what common mechanism? A) Soil compaction B) Environmental pollution C) Loss of animal habitat D) Vegetation removal
D) Vegetation removal
Which of the following statements is an example of a negative feedback loop? A) Warmer and drier climatic conditions lead to more fires, which in turn release more CO2, which could lead to more warming. B) Warmer conditions in the tundra increase decomposition rates, so more carbon is released from stored soil organic matter into the atmosphere, which leads to more warming. C) A fire generates more heat, which increases combustion, which would cause more fire. D) Warmer conditions lead to increased photosynthetic rates and hence an increase in uptake of CO2, which could decrease the temperature.
D) Warmer conditions lead to increased photosynthetic rates and hence an increase in uptake of CO2, which could decrease the temperature
Why are gene duplications, such as those in the Hox loci, often associated with evolutionary divergence? A) Gene duplications arise through hybridization of two species, giving rise to a new species; the combined genome carries two copies of a gene instead of one. B) Gene duplications arise in response to natural selection for diversification within a lineage. When a new species needs a new gene to adapt to a novel environment, it can produce a gene duplication to enable its adaptation. C) Having two copies of a gene means having twice as much gene product; as a result, rate limitations are relaxed, and the organism can evolve a new body plan. D) When there is only one copy of a gene, natural selection may purge a mutation, preventing it from performing a new function. Selection on the second copy may be relaxed because the first copy is producing all necessary gene products. Mutations conferring new properties may accumulate in the second copy.
D) When there is only one copy of a gene, natural selection may purge a mutation, preventing it from performing a new function. Selection on the second copy may be relaxed because the first copy is producing all necessary gene products. Mutations conferring new properties may accumulate in the second copy.
Which of the following is true of seedless vascular plants? A) Small, non-vascular plants dominated the Carboniferous period. B) Extant seedless vascular plants are larger than the extinct varieties. C) Sphagnum is an economically and ecologically important example of a seedless vascular plant. D) Whole forests were dominated by large, seedless vascular plants during the Carboniferous period.
D) Whole forests were dominated by large, seedless vascular plants during the Carboniferous period.
The average family has less than two children in the United States today, but it was much higher a couple of generations ago. Why might this be? A) The carrying capacity of Earth can no longer support more children. B) Due to increased population size of the United States, competition for resources is greater. C) More infant children survive today than previously. D) Women have access to birth control and choose to have fewer children.
D) Women have access to birth control and choose to have fewer children.
One reason areas near the equator get more rainfall than areas about 30 degrees north or south latitude do is that __________. A) air near the equator sinks, causing rain to fall B) air near the equator is more likely to be drier, so it easily picks up water vapor C) air near the equator rises, warming as it rises and increasing its ability to hold water vapor D) air near the equator rises, cooling as it rises and losing its ability to hold water vapor
D) air near the equator rises, cooling as it rises and losing its ability to hold water vapor
Many pharmaceuticals have been derived from land plants. These chemicals are used in plants mainly as __________. A) structural components B) a source of energy C) reproductive structures D) defense against predators and parasites
D) defense against predators and parasites.
Cladistic methods of phylogenetics depend on __________. A) using gene sequence data to compute nearest neighbor distances B) using numerical methods to compute overall similarity using both ancestral and derived traits C) computing genetic distances among a group of species using phenotypic data D) identifying monophyletic groups based on shared, derived characteristics
D) identifying monophyletic groups based on shared, derived characteristics.
Angiosperm double fertilization is thusly named because it features the formation of __________. A) one embryo from two eggs fertilized by a single sperm cell B) one embryo from one egg fertilized by two sperm cells C) two embryos from one egg and two sperm cells D) one embryo involving one sperm cell and an endosperm involving a second sperm cell
D) one embryo involving one sperm cell and an endosperm involving a second sperm cell.
To recycle nutrients, an ecosystem must have, at a minimum, __________. A) producers, primary consumers, and decomposers B) producers C) producers, primary consumers, secondary consumers, top carnivores, and decomposers D) producers and decomposers E) producers, primary consumers, secondary consumers, and decomposers
D) producers and decomposers
Generalized global air circulation and precipitation patterns are caused by __________ A) mountain ranges that deflect air masses containing variable amounts of moisture B) polar, cool, moist, high-pressure air masses that move along the surface, releasing precipitation along the way to the equator, where they are heated and dried C) the revolution of Earth around the sun D) rising, warm, moist air masses that cool and release precipitation as they rise to high altitude and then cool and sink back to the surface as dry air masses after moving north or south of the tropics E) air masses that are dried and heated over continental areas that rise, cool aloft, and descend over oceanic areas, followed by a return flow of moist air from ocean to land, delivering high amounts of precipitation to coastal areas
D) rising, warm, moist air that cool and release precipitation as they rise to high altitude and then cool and sink back to the surface as dry air masses after moving north or south of the tropics.
The structural integrity of bacteria is to peptidoglycan, as the structural integrity of plant spores is to __________. A) cellulose B) secondary compounds C) lignin D) sporopollenin
D) sporopollenin
An area with moderate annual overall temperature, moderate variation in temperature, and moderate annual variation in rainfall but relatively low overall rainfall would be __________. A) temperate forest B) desert C) tropical wet forest D) temperate grassland
D) temperate grassland
Biologists identify and characterize climate in an area primarily by analyzing __________. A) the area's altitude and average annual temperature and precipitation B) the area's species composition and average annual temperature and precipitation C) the area's global longitude and altitude D) the area's average annual temperature and precipitation and annual variation in temperature and precipitation
D) the area's average annual temperature and precipitation and annual variation in temperature and precipitation.
If the direction of Earth's rotation reversed, the most predictable effect would be __________. A) the elimination of ocean currents B) a loss of seasonal variation at high latitudes C) no more night and day D) winds blowing from west to east along the equator E) a big change in the length of the year
D) winds blowing from west to east along the equator.
Which of the following statements is true? A) At any point in time, it is impossible for consumers to outnumber producers in an ecosystem. B) The main reservoir of ecosystem phosphorous is the atmosphere. C) There has been a well-documented increase in atmospheric nitrogen over the past several decades. D) An ecosystem's trophic structure determines the rate at which energy cycles within the system. E) Chemoautotrophic prokaryotes near deep-sea vents are primary producers.
E) Chemoautotrophic prokaryotes near deep-sea vents are primary producers
Islands are well known for having many endemic species (found nowhere else in the world). What is a likely explanation for this pattern? A) Islands are often distant from mainlands and, therefore, island species cannot emigrate to other areas. B) Humans bring partly or fully domesticated species with them when they arrive on islands. C) Islands are more complex habitats than continents, so they have more niches for specialization. D) The type of organism that is a good colonizer has more than the average amount of genetic variability, so it is more likely to speciate. E) Colonizers encounter fewer competitors on an island, so they can diversify more easily.
E) Colonizers encounter fewer competitors on an island, so they can diversify more easily.
Why does a vegetarian leave a smaller ecological footprint than an omnivore? A) Fewer animals are slaughtered for human consumption. B) Vegetarians require less protein than omnivores. C) Vegetarians need to ingest less chemical energy than omnivores. D) There is an excess of plant biomass in all terrestrial ecosystems. E) Eating meat is a less efficient way of acquiring photosynthetic productivity.
E) Eating meat is a less efficient way of acquiring photosynthetic productivity.
According to the latest hypotheses, why do evergreens predominate in cold environments? A) Evergreens do not shed their leaves and thus do not need as many soil nutrients. B) Evergreens photosynthesize year-round. C) Evergreens do not shed their leaves and thus do not need as many soil nutrients. Evergreens photosynthesize year-round. D) Evergreens begin photosynthesizing in early spring, even before the snow melts. E) Evergreens begin photosynthesizing in early spring, even before the snow melts. Evergreens do not shed their leaves and thus do not need as many soil nutrients.
E) Evergreens begin photosynthesizing in early spring, even before the snow melts. Evergreens do not shed their leaves and thus do not need as many soil nutrients.
Approximately 1 percent of the solar radiation that strikes a plant is converted into the chemical bond energy of sugars. Why is this amount so low? A) Approximately 99 percent of the solar radiation is reflected. B) Only the green wavelengths are absorbed by plants for photosynthesis. C) Most solar energy strikes water and land surfaces. D) Approximately 99 percent of the solar radiation is converted to heat energy. E) Only a small percentage of the wavelengths of light are absorbed by photosynthetic pigments.
E) Only a small percentage of the wavelengths of light are absorbed by photosynthetic pigments.
Which trophic level is most vulnerable to extinction? A) Decomposer level B) Secondary consumer level C) Primary consumer level D) Producer level E) Tertiary consumer level
E) Tertiary consumer level
Population ecologists follow the fate of same-age cohorts to determine __________. A) a population's carrying capacity B) if a population's growth is cyclic C) if a population is regulated by density-dependent processes D) the factors that regulate the size of a population E) the birth rate and death rate of each group in a population
E) The birth rate and death rate of each group in a population
A fish swimming into an estuary from a river would have which of the following as its greatest physiological challenge? A) The high water flow would make the fish expend more energy. B) The low oxygen content would give the fish difficulty in swimming aerobically. C) The flux of nutrients washing into the estuary would give the fish difficulty in swimming aerobically. D) The temperature change would stress the fish by denaturing its proteins. E) The change in water solute content would challenge the osmotic balance of the fish.
E) The change in water solute content would challenge the osmotic balance of the fish.
The gradual evolution of oxygen changed Earth's environment dramatically. Which of the following took advantage of the presence of free oxygen in the oceans and atmosphere? A) The persistence of some animal groups in anaerobic habitats B) The evolution of chloroplasts after early protists incorporated photosynthetic cyanobacteria C) The evolution of photosynthetic pigments that protected early algae from the corrosive effects of oxygen D) The evolution of multicellular eukaryotic colonies from communities of prokaryotes E) The evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules
E) The evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules.
The discovery of pollen in various sedimentary layers has allowed paleontologists to correlate the existence of ancient animals with the vegetation on which they often subsisted. The preservation of pollen in sedimentary layers is an example of a/n _____________. A) permineralized fossil B) cast fossil C) trace fossil D) compression fossil E) intact fossil
E) intact fossil
Trees are not usually found in the tundra biome because of __________. A) acidic soils B) over-browsing by musk ox and caribou C) insufficient annual precipitation D) extreme winter temperatures E) permafrost
E) permafrost
A node that depicts an ancestral branch dividing into three or more descendant branches is called a __________. A) fork B) root C) branch D) tip E) polytomy
E) polytomy
Imagine some cosmic catastrophe jolts Earth so that its axis is changed to 0 degrees (straight up and down). The most obvious effect of this change would be __________. A) a decrease in temperature at the equator B) the elimination of tides C) an increase in the length of a year D) an increase in the length of night E) the elimination of seasonal variation
E) the elimination of seasonal variation