Biology Exam 2: All Mastering Questions
Assuming that r has a positive value, in the formula dN/dt = rmaxN (K - N)/K, the factor rN tends to cause the population to __________.
grow increasingly rapidly
A population that is growing logistically __________.
grows fastest at an intermediate population density
The greatest cause of extinction of species today is __________. habitat alteration global warming predation the greenhouse effect overharvesting
habitat alteration
Mining and forestry result in _________.
habitat loss
The sum of a species' use of the biotic and abiotic resources in its environment is called __________.
its ecological niche
Life history traits that are favored at high population densities are known as _________.
k-selection
Which of the following is an example of an abiotic factor in an ecosystem? disease predation competition temperature
temperature
How many genes are present in the human genome?
tens of thousands
An antagonistic social interaction used to defend a bounded physical space is called __________.
territoriality
A human who just ate a hamburger is eaten by a shark while swimming. The shark is acting as a _____.
tertiary consumer the shark ate the human that ate the cow that ate the grass
The flower fly resembles a honeybee, but the flower fly has no stinger. This is an example of __________.
batesian mimicry
Which of these organisms has a survivorship curve similar to that of oysters? robins grasses elephants humans cats
grasses
he branch of biology that is important in controlling overharvesting is _________.
molecular biology
The symbols +, -, and 0 are to be used to show the results of interactions between individuals and groups of individuals. The symbol + denotes a positive interaction, - denotes a negative interaction, and 0 denotes where individuals are not affected by interacting. The first symbol refers to the first organism mentioned. What interactions exist between cellulose-digesting organisms in the gut of a termite and the termite?
+/+
A population of ground squirrels has an annual per capita birth rate of 0.06 and an annual per capita death rate of 0.02. Using these birth and death rates, calculate an estimate of the total number of individuals added to (or lost from) a population of 1,000 individuals in one year.
40 individuals added
Consider the food chain of grass → grasshopper → mouse → snake → hawk. About how much of the chemical energy fixed by photosynthesis of the grass (100 percent) is available to the hawk? 1% 10% 0.1% 0.01%
0.01%
In a population that is in Hardy-Weinberg equilibrium, 64% of the individuals express the recessive phenotype for a particular gene locus. What is the expected frequency of the dominant allele in this population?
0.2
In a population that is in Hardy-Weinberg equilibrium, 64% of the individuals express the recessive phenotype for a particular gene locus. What is the expected frequency of the recessive allele in this population?
0.8
Darwin's four postulates can be summarized as follows:
1. Individuals in a population vary in the traits they possess. 2. Some trait differences are heritable. 3. Survival and reproductive success are variable among individuals in a population. 4. Individuals with certain traits are more likely to survive and reproduce.
A recessive allele on the X chromosome is responsible for red-green color blindness in humans. A woman with normal vision whose father is color blind marries a color-blind male. What is the probability that this couple's first son will be color blind?
1/2
Suppose a BB female mouse mates with a Bb male mouse. Which of the following represents the probabilities of each genotype occurring among their offspring?
1/2 BB, 1/2 Bb
Approximately how many kilograms (kg) of carnivore (secondary consumer) biomass can be supported by a field plot containing 1000 kg of plant material?
10
Suppose researchers marked 800 turtles and later were able to trap a total of 300 individuals in that population, of which 150 were marked. What is the estimate for total population size?
1600
If another island were present in the Caribbean that was about 1000 square miles in size, how many species of amphibians and reptiles would you expect to find on it? Choose the most likely number from the options below.
19
In human gamete production there is an average of _____ crossover events per chromosome pair.
2-3
In a certain group of people, 4% are born with sickle-cell disease (homozygous recessive). If this group is in Hardy-Weinberg equilibrium, what percentage of the group is heterozygous for the sickle hemoglobin allele?
32% The 4% born with sickle-cell disease are homozygous for the sickle hemoglobin allele, so q2 = 0.04 and q = 0.2. Because p = 1 - q, p = 0.8. The heterozygotes would be equal to 2pq, or 0.32 (32%).
What is the result when a diploid cell undergoes meiosis?
4 haploid cells
Starting from a single individual, what is the size of a population of bacteria at the end of a 2-hour time period if they reproduce by binary fission every 20 minutes? (Assume unlimited resources and no mortality.)
54
You are doing a mark-recapture experiment to determine the population size of the MendAliens living on an island in my back yard. Initially, you catch and mark 130 MendAliens, which you then release. Next, you capture 90 MendAliens, of which 20 are marked. What is your estimate of the population size of MendAliens living on the island in my back yard?
585 To get the population size N, multiply the number marked in the first catch, M1, by the total number caught in the second catch, C, and divide that by the number of marked recaptures in the second catch, M2: N = (M1 x C) / M2 Or: (130 x 90) / 20 = 585.
A gene that has two alleles, A and a, is located on the same chromosome as a second gene that also has two alleles, B and b. Suppose a diploid individual has alleles AB on one copy of this chromosome and alleles ab on the other copy of this chromosome. For this individual, select the pair of recombinant genotypes that could result if crossing over occurs between these two chromosomes.
Ab and aB
Which of the following statements correctly describe(s) characteristics of genetic drift?
All of the listed responses are correct. It is significant in small populations. It can cause allele frequencies to change at random. It can lead to a loss of genetic variation in a population. It can cause harmful alleles to become fixed in a population.
Which of the following people developed the idea known as the scala naturae, or scale of nature? Aristotle Darwin Wallace Hutton Lyell Linnaeus
Aristotle
What Central American country is a world leader in zoned reserves?
COSTA RICA
The modern idea of extinction as a common occurrence in Earth's history was first proposed in the early 19th century writings of __________. Cuvier Lamarck Aristotle Wallace Lyell
Cuvier
Detritus is composed of _____.
DEAD ORGANIC MATTER AND EXCRETED WASTES
Eukaryotic chromosomes are composed of which of the following macromolecules?
DNA and proteins
How did Hutton and Lyell's ideas influence Charles Darwin's thinking?
Darwin reasoned that the earth must be very old and that slow, subtle processes could produce substantial biological changes
Paleontology, the study of fossils, was developed by __________.
Georges Cuvier
Often the growth cycle of one population has an effect on the cycle of another. As moose populations increase, for example, wolf populations also increase. Thus, if we are considering the logistic equation for the wolf population, dNdt=rN(K−N)K, which of the factors accounts for the effect of the moose population? N r K rN
K
Which one of these is a nitrite? NH2 PO4 - NH4 - NO3 - NO2 -
NO2-
Which one of these is a nitrate? NH4 - SH NO2 - NH2 NO3 -
NO3-
Which of the following statements about natural selection is true? Natural selection favors individuals that reproduce more than others. Natural selection is a process whereby genes are selected randomly for preservation in the next generation. Natural selection occurs in opposition to evolution. Natural selection can be used by farmers to generate organisms with desirable traits.
Natural selection favors individuals that reproduce more than others
The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data? Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. Humans and bats evolved by natural selection, and whales evolved by Lamarckian mechanisms. Forelimb evolution was adaptive in people and bats, but not in whales. Genes mutate faster in whales than in humans or bats. Whales are not properly classified as mammals.
Natural selection in an aquatic environment resulted in significant change to whale forelimb anatomy
All animals can trace their lineage to a common ancestor that lived in the _____.
Neoproterozoic era
According to bottom-up and top-down control models of community organization, which of the following expressions would imply that an increase in the size of a carnivore (C) population would negatively impact its prey (P) population, but not vice versa? The arrows between species indicate a negative impact toward the population at the arrowhead. P → C C ↔ P P C P C → P
P C
What do animals ranging from corals to monkeys have in common? presence of Hox genes a mouth and an anus some type of body symmetry number of embryonic tissue layers
PRESENCE OF HOX GENES
What is the difference between an F+ donor and an Hfr donor?
The Hfr donor has an F factor integrated into its main chromosome, but the F+ donor does not
SAR is a group defined by DNA similarities. This grouping represents ________.
a hypothesis about evolutionary history
At what level does gene variability quantify genetic variation?
WHOLE-GENE
In a phylogenetic tree, a lineage that diverges from all other members of its group early in the evolutionary history of the group is described as
a basal taxon
Which of the following features is not unique to either prokaryotic or eukaryotic cells? a nucleus a nucleoid a cell wall a mitochondrion
a cell wall
Mutations are always __________. bad good neutral a change in an individual's DNA
a change in an individual's DNA
Which of the following statements is in accordance with F. E. Clements' view that species in a community function as an integrated unit? Species composition is determined by island size and distance from the mainland. Food chains are not isolated units but are linked together in food webs. Most communities are chance assemblages of species found together because they have similar abiotic requirements. Most communities are not at equilibrium. A community at a particular site has only one stable equilibrium.
a community at a particular site has only one stable equilibrium
Which of the following organisms could be produced by artificial selection? A cow that produces a large quantity of milk. A dog that serves as the "eyes" for a blind individual. A chimpanzee that communicates through sign language. A rabbit that is housebroken.
a cow that produces a large quantity of milk
The reason for the decline of the greater prairie chicken in Illinois was _________. a decrease in fertility due to lack of genetic diversity in the population a decrease in fertility due to lack of breeding grounds their migration to Virginia that exotic species outcompeted them for resources
a decrease in fertility due to lack of genetic diversity in the population
Which of the following is radially symmetrical? an automobile a dog a submarine sandwich a doughnut a spoon
a doughnut
The last common ancestor of all animals was probably a _____.
a flagellated protist
Life tables typically follow the fate of a cohort, a __________.
a group of individuals who are the same age
Which of the following anatomical features of the 3.2-million-year-old Australopithecus fossil known as "Lucy" suggest she was a bipedal hominid? a much shorter hip bone that is broader from front to back and wraps around the side a hairless face the absence of a prehensile tail a large brain
a much shorter hip bone that is broader from front to back and wraps around the side
Consider a population whose growth over a given time period can be described by the exponential model: dN/dt = rN. Select the correct statement about this population. A population with a positive value of r will grow exponentially. A population with an r of 0.1 will decrease over time. A population with an r of 0 will have no births or deaths during the time period under consideration.
a population with a positive value of r will grow exponentially
According to the hypothesis of serial endosymbiosis, which of the following was a key initial step in the origin of mitochondria? A prokaryotic host cell engulfed an aerobic, heterotrophic bacterium. A eukaryotic host cell engulfed an aerobic, photosynthetic bacterium. A eukaryotic host cell engulfed an aerobic, heterotrophic bacterium. A prokaryotic host cell engulfed an aerobic, photosynthetic bacterium.
a prokaryotic host cell engulfed an aerobic, heterotrophic bacterium
In which of the following situations would you expect to find the largest number of r-selected individuals? a sand dune community south of Lake Michigan an old-growth forest with large, mature trees a coral reef community off the coast of Mexico a recently abandoned agricultural field in Colorado
a recently abandoned agricultural field in Colorado
Ignoring migration, the age structure diagram of a human population likely to maintain a relatively stable size will have what shape? Both a pyramid and a rectangle tapering toward the top result in a population that remains stable in size. inverted pyramid pyramid a rectangle tapering toward the top Both an inverted pyramid and a rectangle tapering toward the top result in a population that remains stable in size.
a rectangle tapering toward the top such a population is expected to have relatively stable size
Chimpanzees have a relatively low birth rate. They care for their young, and most chimps live a long life. The chimp survivorship curve would look like ___________.
a relatively flat line that drops steeply at the end
Consider the following mutations to the nucleotide sequence of a gene. Which of these mutations would not alter the reading frame of the gene's genetic message? a single nucleotide-pair insertion a single nucleotide-pair substitution a single nucleotide-pair deletion a deletion that removes 4 nucleotides
a single nucleotide-pair substitution
A graph that plots the numbers of individuals who are alive at particular ages is called _________.
a survivorship curve
Which of the following statements best describes the overall process of descent with modification? Similarity between two species results from genetic drift in small populations. A trait present in an ancestral organism is modified by natural selection over time in descendants of that ancestor. Similarity between two species results from convergent evolution. Natural selection leads to the evolution of similar features in independent evolutionary lineages.
a trait present in an ancestral organism is modified by natural selection over time in descendants of that ancestor
Among protostomes, which morphological trait has shown the most variation? number of embryonic tissue types (diploblasty versus triploblasty) type of body cavity (coelom versus pseudocoelom versus no coelom) type of symmetry (bilateral versus radial versus none) type of development (protostome versus deuterostome)
a type of body cavity (coelom versus pseudocoelom versus no coelom)
Which term describes a trait that increases an individual's ability to survive in a particular environment? Adaptation Evolution Fitness Heritability
adaptation
Whatever its ultimate cause(s), the Cambrian explosion is a prime example of _____.
adaptive radiation
Which of the following would be considered an example of bioremediation? adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen availability using a bulldozer to regrade a strip mine adding fertilizer to soil poor in nutrients to increase plant growth dredging a river bottom to remove contaminated sediments
adding nitrogen-fixing microorganisms to a degraded ecosystem to increase nitrogen availability
Predict the most likely outcome of fertilizing areas of ocean with iron.
an increase in diatom populations that will contribute to reducing atmospheric CO2
A population of zooplankton is exposed to a small number of predatory fish that feed on the larger-sized (adult) zooplankton. Which of the following predictions would most likely occur based on the principles of natural selection? Adult zooplankton will start to reach sexual maturity when they are still relatively small. The predatory fish will evolve smaller mouths so that they do not drive their prey to extinction. The zooplankton will become sexually mature at larger sizes. The predatory fish will evolve poor eyesight so as to preserve their food supply. The first and the third listed responses are both good predictions.
adult zooplankton will start to reach sexual maturity when they are still relatively small
Oyster populations are primarily, if not exclusively, composed of _____.
adults young oysters have a very high mortality rate
Except for modern ethnic groups in ______, the majority of humans appear to have traces of Neanderthal DNA in their genome.
africa
Which of these removes carbon from the atmosphere? logging trees rabbits burning fossil fuels, such as oil bobcats algae
algae
The gene pool of a population consists of __________.
all copies of every type of allele at every locus in all members of the population
During periods of rapid environmental change, what may happen to a species that was well-suited to the former environment? All of the listed responses are correct. The species may go extinct. Individuals with particular traits that provide an advantage in the new environment will have higher reproductive success. The population may change so much in adapting to the new environment that it is considered a new species. Traits that were favorable in the original environment may be detrimental in the new environment.
all of the listed responses are correct
Natural selection leads to adaptation, but there are many organisms on Earth that exhibit characteristics that are less than ideal for their environment. Which of the following statements correctly explain(s) this? All of the listed responses are correct. Selection can act only on existing variations. Evolution is limited by historical constraints. Adaptations are often compromises. Chance, natural selection, and the environment interact.
all of the listed responses are correct
Which of the following is correct regarding natural selection? All of the listed responses are correct. Natural selection is a process in which individuals that have certain inherited traits tend to survive and reproduce at higher rates than do individuals without those traits. Over time, natural selection can increase the correspondence between organisms and their environments. If an environment changes, or if individuals move to a new environment, natural selection may result in adaptation to these new conditions, sometimes giving rise to new species. Individuals do not evolve; populations do. None of the listed responses is correct.
all of the listed responses are correct
All known organisms transcribe genetic information to protein molecules via the same genetic code. This finding strongly supports the hypothesis that __________.
all organisms are descended from a single common ancestor
Which of the following statements correctly describes a population in Hardy-Weinberg equilibrium?
allele and genotype frequencies in the population will remain constant from generation to generation
The life cycle called __________ in plants has two multicellular stages: the __________ and the __________.
alteration of generations; haploid gametophyte; diploid sporophyte
Nitrifying bacteria convert _____ to _____.
ammonium, nitrites
Which of the following groups is most severely threatened with extinction? Amphibians Birds Mammals Plants Fishes
amphibians
A leech that attaches itself to a swimmer is an example of __________.
an ectoparasite
Insect wings may have begun to evolve as lateral extensions of the body that were used as heat dissipaters for thermoregulation. When they had become sufficiently large, these extensions became useful for gliding through the air. Additional selection refined them as flight-producing wings. If this hypothesis is correct, modern insect wings would be an example of _____.
an exaptation
Commensalism is ________.
an interaction between species that benefits one of the species but neither harms nor helps the other species
facilitation is _________.
an interaction where species have positive effects on the survival and reproduction of other species without necessarily living in the direct and intimate contact of symbiosis
Which of the following is true of secondary endosymbiosis? It is indicated by the presence of a double membrane surrounding the endymbiont. An organism containing one endosymbiont engulfs another organism, and that organism becomes an endosymbiont. It is indicated by the presence of a nucleomorph. An organism containing an endosymbiont is engulfed by another organism and becomes an endosymbiont. It is indicated by the presence of a mixotroph.
an organism containing an endosymbiont is engulfed by another organism and then becomes an endosymbiont
Which of the following statements supports the conclusion that the common ancestor of modern chimps and modern humans lived around 7 million years ago? Analysis of modern human and modern chimpanzee protein and DNA sequences suggests that their lineages diverged about 7 million years ago. Scientists estimate that it would take about 7 million years for chimps to evolve into humans. Stone tools have been found that date back about 7 million years. Scientists estimate that it takes about 2.5 million years for brains to double in volume, so it would take about 7 million years to go from 300 cc (early hominid brain size) to 1500 cc (modern human brain size).
analysis of moderm human and modern chimpanzee protein and DNA sequences suggests that their lineages diverged about 7 mil. years ago
Centromeres divide and sister chromatids become full-fledged chromosomes during _____.
anaphase
Arthropods invaded land about 100 million years before vertebrates. This fact most clearly implies that ________. extant terrestrial arthropods are better adapted to terrestrial life than are extant terrestrial vertebrates vertebrates evolved from arthropods arthropods have had more time to coevolve with land plants than have vertebrates arthropods evolved before vertebrates did
anthropods have had more time to coevolve with land plants than have vertebrates
Treehoppers (a type of insect) produce honeydew, which ants use for food. Treehoppers have a major predator, the jumping spider. Researchers hypothesized that the ants would protect the treehoppers from the spiders. In an experiment, researchers followed study plots with ants removed from the system and compared them to a control plot. From the figure, what can you conclude?
ants do somehow protect the treehoppers from spiders
Which of these primate groups is most closely related to humans? apes Old World monkeys lorises prosimians New World monkeys
apes
Soon after the coelom begins to form, a researcher injects a dye into the coelom of a deuterostome embryo. Initially, the dye should be able to flow directly into the _____.
archenteron
What did scientists learn from other fossils found in the same sediment layer as Ardi?
ardi lived in a woodland habitat
Somatic cells in animals differ from gametes in that somatic cells __________.
are all of the cells of the body except for the gametes and their precursors
Sister chromatids differ from nonsister chromatids in that sister chromatids __________.
are products of the S phase of the cell cycle and are two copies of one chromosome
The breeding of plants and animals for particular traits by humans is called __________. artificial selection natural selection sexual recombination paleontology homology
artificial selection
Which of the following statements are true of logistic growth? As the population approaches carrying capacity, it grows more slowly. When the population reaches carrying capacity, it stops growing. As the population approaches carrying capacity, it grows more rapidly. The population grows at a steady rate.
as the population approaches carrying capacity, it grows more slowly when the population reaches carrying capacity, it stops growing
A clone is the product of __________.
asexual reproduction and mitosis
Consider a population whose growth can be described by the logistic growth model: dN/dt = rmaxN[(K − N)/K]. Which of the following statements about this population is true? K is a constant value. At low values of N, the logistic growth and exponential growth (dN/dt = rN) models predict similar population growth. rmax declines as N increases.
at low values of N, the logistic growth and exponential growth models predict similar population growth
You are a paleoanthropologist. You uncover the skull of a hominid estimated to be 3.3 million years old. Which of the following would be best for you to initially compare it to? Australopithicus afarensis Neanderthals Australopithicus prometheus Australopithicus deyiremeda
australopithicus afarensis
Which type of selection maintains stable frequencies of two or more phenotypic forms in a population?
balancing selection
A small population that inbreeds may ________. be drawn into an extinction vortex become a founder group become genetically imprinted have increased fitness reduce harmful genes
be drawn into an extinction vortex
Ozone is __________. beneficial in the upper atmosphere harmful in the upper atmosphere beneficial in the lower atmosphere harmful in the upper atmosphere and beneficial in the lower atmosphere beneficial in both the upper atmosphere and the lower atmosphere
beneficial in the upper atmosphere
A relatively small area with numerous endemic species and a large number of endangered or threatened species is called a _________.
biodiversity hot spot
A group of populations of different species living close enough to interact is called a __________.
biological community
The natural human connection to nature and other forms of life is called __________.
biophilia
Of the following, which is the most inclusive level of organization in nature? ecosystem population community cell biosphere
biosphere
In what respect do hominins differ from all other anthropoids?
bipedal posture
Which of the following factors does not contribute to environmental resistance? weather conditions birth rate environmental toxins competition for space competition for food
birth rate
Which processes increase a population's size? Deaths and immigration Births and immigration Births and deaths Deaths and emigration
births and immigration
DNA was isolated from Neanderthal ____ and sequenced so that it could be compared to modern human DNA.
bone fragments
A population that grows rapidly at first and then levels off at carrying capacity can be modeled __________.
by a logistic equation
How do scientists know that the hominid called "Ardi" is about 4.4 million years old?
by using radiometric dating techniques on the volcanic deposits found above and below the layer containing Ardi
Scientists from Russia and Japan are attempting to resurrect the extinct woolly mammoth __________.
by using well-preserved bone marrow from the thigh of a frozen mammoth
The earliest ancestors of about half of all extant animal phyla can be traced back to the _____ explosion.
cambrian
Which of the following statements about the movement of nutrients through an ecosystem is true? Carbon cycles between the atmosphere and living biomass. Nutrients in the soil can be eaten and used directly by animals. A biogeochemical cycle is the path that an element takes as it moves from organism to organism. An organism transfers only its energy to the organism that eats it.
carbon cycles between the atmosphere and living biomass
How does carbon move from the biota to the atmosphere?
carbon dioxide is released during cellular respiration
How have humans altered the global carbon cycle?
carbon inputs into the atmosphere have risen
The maximum population size that a particular environment can sustain is called the _________.
carrying capacity
What are population dynamics?
changes in populations throughout time
The larvae of some insects are merely small versions of the adult, whereas the larvae of other insects look completely different from adults, eat different foods, and may live in different habitats. Which of the following is most directly involved in the evolution of these variations in metamorphosis?
changes in the homeobox genes controlling early development
_________ is the tendency of characteristics to diverge more in sympatric than in allopatric populations.
character displacement
Which of the following is true? Chimpanzees and hominids share a common ancestor. Hominids evolved from chimpanzees. Chimpanzees evolved from hominids. Chimpanzees are hominids.
chimpanzees and hominids share a common ancestor
Which of the following would you classify as something other than an animal? jellyfish coral choanoflagellate sponge
choanoflagellate
The fact that choanoflagellates and collar cells of sponges resemble each other supports the inference that ________.
choanoflagellates and sponges are sister groups
How do climatologists estimate past atmospheric CO2 concentrations?
climatologists measure the CO2 concentrations in air bubbles trapped in glacial ice
__________ are a group of genetically identical individuals produced by a process called __________.
clones; asexual reproduction
Organisms that live in a homogenous abiotic environment and cooperate to avoid being eaten would likely show a(n) __________ pattern of dispersion. clumped continuous uniform even random
clumped
A researcher is trying to construct a molecular-based phylogeny of the entire animal kingdom. Assuming that none of the following genes are absolutely conserved, which of the following would be the best choice on which to base the phylogeny?
collagen genes
Plasmodium exhibits consumption in its interactions with mosquitoes and humans. Which process is not an example of consumption? Herbivory. Commensalism. Parasitism. Predation.
commensalism
According to the nonequilibrium model of community diversity, ________.
communities are constantly changing after being influenced by disturbances
Brown et al. and Morwood et al. reported in 2004 that they had found skeletal remains of a previously unknown type of hominin, now dubbed Homo floresiensis, on the Indonesian island of Flores. These hominins were small (approximately 1 meter tall) with small braincases (approximately 380 cubic centimeters) as compared with other hominins. The remains of H. floresiensis were found alongside handmade stone tools and the remains of dwarf elephants that also inhabited the island, suggesting that H. floresiensis was able both to make tools and to coordinate the hunting of animals much larger than itself. H. floresiensis is estimated to have lived at the site where the remains were found from at least 38,000 years ago to 18,000 years ago. Which would be the most feasible method of figuring out to which other hominin species H. floresiensis was most closely related? Compare the skeletal morphology of H. floresiensis to that of each of the other hominin species. Compare the type of prey hunted by H. floresiensis to that hunted by each of the other hominin species. Compare the average body size of H. floresiensis to that of each of the other hominin species. Compare the estimated life span of H. floresiensis to that of each of the other hominin species.
compare the skeletal morphology of H. floresiensis to that of each of the other hominin species
Which of the following causes populations to shift most quickly from an exponential to a logistic population growth? removal of predators decreased death rate favorable climatic conditions competition for resources
competition for resources
Which of the following typically produces a recombinant F+ recipient cell?
conjugation between an F+ cell and an F- cell
Which of the following could cause DNA from the main chromosome of a donor cell to be incorporated into the main chromosome of the recipient cell?
conjugation between an Hfr cell and an F- cell
What is one viable solution to help increase the effective size and genetic variation in the grizzly bear population in Yellowstone National Park? Conservation biologists could introduce just two new bears each decade from another population. Conservation biologists could increase genetic diversity by selectively breeding bears within the Yellowstone population that have not bred together before. Conservation biologists could introduce another population of bears of equal size to Yellowstone. The park should be closed to humans until the bear population can revive. Conservation biologists could develop methods to help bears locate each other for breeding.
conservation biologists could introduce just two new bears each decade from another population
The science that integrates all aspects of biology is called _________.
conservation biology
What did the researchers do that caused red-cockaded woodpeckers to form new breeding groups at new sites?
constructed nesting cavities at new sites
Somatic cells in humans differs from gametes in that human somatic cells __________.
contain two sets of each of the 23 chromosomes types
Consider two very distantly related species, Species A and Species B. These species live in distinct but similar environments and share a trait that improves their survival and reproduction in their respective environments. Which of the following is the most likely reason that Species A and Species B share this trait?
convergent evolution
Even though rodents known as sugar gliders and flying squirrels are members of distinctly different groups of organisms and live on different continents, they possess similar characteristics. This is an example of __________. convergent evolution homology adaptation acquired characteristics use and disuse All of the listed responses are correct
convergent evolution
Nitrifying bacteria participate in the nitrogen cycle mainly by _____.
converting ammonium to nitrate, which plants absorb
One of the most impressive models of sustainable development can be seen in the __________.
costa rican zoned reserves
Which of the following scenarios would provide the most accurate data on population density? Count the number of pine trees in several randomly selected 10-meter-square plots and extrapolate this number to the fraction of the study area these plots represent. Calculate the difference between all of the immigrants and emigrants to see if the population is growing or shrinking. Count the number of nests of a particular species of songbird and multiply this by a factor that extrapolates these data to actual animals. Use the mark-recapture method to estimate the size of the population.
count the number of pine trees in several randomly selected 10-meter-square plots and extrapolate this number to the fraction of the study area these plots represent
Flounder is a type of fish that looks like the seafloor. This is an example of __________. cryptic coloration Müllerian mimicry warning coloration character displacement Batesian mimicry
cryptic coloration
The chloroplasts of land plants are thought to have been derived according to which evolutionary sequence?
cyanobacteria --> green algae --> land plants
Which of the following would most likely be an example of a density-independent factor limiting population growth? Daily temperature extremes Food availability Diseases Accumulation of toxic wastes Parasites
daily temperature extremes
Which of the following would likely do the most decrease toxic algal growth in Lake Erie? Convert nearby wetlands to pasture or croplands. Decrease use of fertilizers in the region. Dredge the lake to about one-half mile offshore. Decrease pesticide use.
decrease use of fertilizers in the region
In the North Pacific, sea otters are keystone predators. A reduction in their numbers has resulted in what changes in the marine community?
decreased community diversity
The difference between density and dispersion is that __________.
density is the number of individuals of a population in a unit area whereas dispersion is the pattern of spacing of individuals of the population
A particular environmental change causes the deaths of 25 individuals in a herd of 100 wild horses, and it kills 50 individuals in a herd of 200 horses. In this case, the growth of a wild horse population is most likely limited by __________. (Assume that the two herds are found in territories of equal size.)
density-independent factor
Which of the following statements about density-independent growth is true? The per-capita rate of increase may exceed rmax during density-independent growth. A population that is experiencing density-independent growth levels off at the environment's carrying capacity. Density-independent growth can continue indefinitely in nature. Density-independent growth is also known as exponential growth.
density-independent growth is also known as exponential growth
Darwin originally defined evolution as __________. descent with modification the passing of acquired characteristics to offspring an individual's ability to adapt to its environment a way to classify organisms based on morphological similarities None of the listed responses is correct.
descent with modification
What is the meaning of Darwin's expression "descent with modification"?
descent with modification refers to evolutionary change over time
An earthworm that feeds on the remains of plants and animals is acting as a _____.
detritivore feeds on the remains of dead organisms
Different finch species have beaks of different shapes and sizes. What do these beak differences tell us?
different finch beak shapes are evidence that finch species adapted to different environments over many generations
Regardless of whether an organism is an animal, a plant, a fungus, or an algal cell, all zygotes are __________ and are formed during the __________ of two __________ gametes.
diploid; fertilization; haploid
Antibiotic resistance in bacteria is an example of which of the following? Directional selection Stabilizing selection Disruptive selection Hardy-Weinberg equilibrium Macroevolution
directional selection
A population of squirrels is preyed on by small hawks. The smaller squirrels can escape into burrows. The larger squirrels can fight off the hawks. After several generations, the squirrels in the area tend to be very small or very large. What process is responsible for this outcome?
disruptive selection
The three levels of biodiversity in the correct order are _________ diversity.
genetic, species, and community/ecosystem
An important challenge to traditional (pre-1860) ideas about species was the observation that seemingly dissimilar organisms such as hummingbirds, humans, and whales have similar skeletal structures. This most directly suggested to biologists that __________. dissimilar organisms might have evolved from a distant, common ancestor only the best-adapted organisms can survive advantageous changes can be passed along to offspring most evolution occurs rapidly following a mass extinction All of the listed responses are correct
dissimilar organisms might have evolved from a distant, common ancestor
Which type of mutation plays the most important role in increasing the number of genes in the gene pool? Duplication Mutations are so rare that there are no mutations that can have such an important effect. Point mutation Rearrangement of gene loci Changes in nucleotide sequence
duplication
Succession of communities occurs because __________.
each existing community changes the environment
A diploid (2n) cell divides by meiosis, producing four daughter cells. Next, each daughter cell divides by mitosis, producing a total of eight granddaughter cells. Which of the following statements about the granddaughter cells is true? Each granddaughter cell is diploid (2n). Each granddaughter cell is haploid (n). Four of the granddaughter cells are genetically identical. All of the granddaughter cells are genetically identical.
each granddaughter cell is haploid (n)
Which of the following is true? Early hominids did not use tools. The definition of tool is too variable to apply to hominids. It is unknown as to whether or not early hominids used tools. Early hominids used tools.
early hominids used tools
Which of the following causes Earth's seasons?
earth's tilt on its axis
Why does a vegetarian leave a smaller ecological footprint than an omnivore?
eating meat is an inefficient way of acquiring photosynthetic productivity
The concept that summarizes the aggregate land and water area required by each person to produce all resources he or she needs and absorb all waste he or she produces is called the _________.
ecological footprint
Crop pollination, water purification, and moderation of weather extremes are just a few examples of __________.
ecosystem services
Which of these organisms has a survivorship curve similar to that of humans? oysters cats robins elephants grasses
elephants
Gray wolves, once the top predators in Yellowstone National Park, were hunted to extinction there in 1926. In 1995, 15 wolves were brought to Yellowstone from Alberta. The wolf population has now grown to 300. The forest community in Yellowstone National Park can be described by a top-down model of community organization. Wolves hunt and eat elk. Elk are herbivores that prefer riparian vegetation (plants growing next to streams and lakes). Ravens, bears, and eagles feed on elk carcasses. How would you expect the return of the wolves to Yellowstone to affect the other species there?
elk populations would decline
organisms found only in specific places in the world are referred to as:
endemic
Which of the following statements best summarizes the process of photosynthesis?
energy from light is converted to chemical energy stored in organic molecules
Which of the following is primarily responsible for limiting the number of trophic levels in most ecosystems? Many primary and higher-order consumers are opportunistic feeders. Energy transfer between trophic levels is usually less than 20 percent efficient. Nutrient cycling rates tend to be limited by decomposition. Decomposers compete with higher-order consumers for nutrients and energy.
energy transfer between trophic levels is usually less than 20 percent efficient
Select the correct statement about the global carrying capacity for the human population Estimates of the global carrying capacity for the human population depend on resource use per capita. It is impossible to calculate the global carrying capacity for the human population. The global carrying capacity for the human population is limitless because technological advances allow food supply to keep up with global population growth.
estimates of the global carrying capacity for the human population depend on resource use per capita
Darwin realized the importance of heritable variation to evolution __________.
even though he never read any of Gregor Mendel's work
When an organism breaks down organic molecules, some of the energy that had been stored as chemical energy is lost as heat. This happens because
every energy transfer or transformation increases entropy
What does it mean to describe evolution as a scientific theory?
evolution is a broad model that is supported by many observations and much experimental evidence
In the context of populations, how do we define evolution?
evolution is a change in a population's allele frequencies over generations
What are two key factors in species richness equatorial-polar gradients?
evolutionary history and climate
Animals that possess homologous structures probably __________.
evolved from the same ancestor
A swim bladder is a gas-filled sac that helps fish maintain buoyancy. The evolution of the swim bladder from lungs of an ancestral fish is an example of _____.
exaptation
Which of the following is true? Excessive algal growth does not happen in fresh or marine water. Excessive algal growth occurs only in fresh water. Excessive algal growth occurs only in marine water. Excessive algal growth can happen in both fresh and marine water.
excessive algal growth can happen in both fresh and marine water
While looking at some seawater through your microscope, you spot the egg of an unknown animal. Which of the following tests could you use to determine whether the developing organism is a protostome or a deuterostome? See whether the embryo _____.
exhibits spiral cleavage or radial cleavage
Which factors permit the human population to continue increasing, without an obvious carrying capacity? expansion of high-density urban areas disease outbreaks famines improvements in medical care
expansion of high-density urban areas improvements in medical care
How does our understanding of genetics today refute Lamarck's principle of the inheritance of acquired characteristics? Experiments in genetics show that traits acquired during an individual's lifetime are not inherited in the way proposed by Lamarck. Experiments in genetics show that traits acquired during an individual's lifetime are inherited in the way proposed by Lamarck. Parts of the body that are not used will deteriorate over time. Parts of the body that are used extensively will become stronger and be passed to offspring. All organisms are perfect and permanent. All of the listed responses are correct.
experiments in genetics show that traits acquired during an individual's lifetime are not inherited in the way proposed by Lamarck
Which of the following traits can be used to differentiate humans from our closest living primate relatives? grasping hands extensive tool use large brain size bipedality (the ability to walk exclusively on two legs)
extensive tool use large brain size bipedality
Stabilizing selection __________. favors intermediate variants in a population prevents mutations from occurring occurs when some individuals migrate to an area with different environmental conditions usually results in two distinct phenotypes occurs only in plants
favors intermediate variants in a population
Which of the following statements explains why male peacocks with brightly colored feathers are more prevalent than those with plain colors? Female peacocks choose the showiest males as mates, causing this trait to be more prevalent in the population. Female peacocks choose the plain-colored males as mates, causing this trait to be more prevalent in the population. Showy males are larger and kill off the plain-colored males. Female mate choice is random, and the showier males happen to be chosen by the females as mates. Male peacocks with showy feathers have no selective advantage over plain-colored males.
female peacocks choose the showiest males as mates, causing this trait to be more prevalent in the population
A population of white-footed mice becomes severely overpopulated in a habitat that has been disturbed by human activity. Sometimes intrinsic factors cause the population to increase in mortality and cause lower reproduction rates to occur in reaction to the stress of overpopulation. Which of the following is an example of intrinsic population control? Clumped dispersion of the population leads to increased spread of disease and parasites, resulting in a population crash. All of the resources (food and shelter) are used up by overpopulation, and much of the population dies of exposure and/or starvation. Owl populations frequent the area more often because of increased hunting success. Females undergo hormonal changes that delay sexual maturation, and many individuals suffer depressed immune systems and die due to the stress of overpopulation.
females undergo hormonal changes that delay sexual maturation, and many individuals suffer depressed immune systems and die due to the stress of overpopulation
Which of the following would lead biologists to believe algae with microcystin were a problem in a Minnesota lake? Finding frogs with extra limbs. Finding numerous dead small animals near the lake. Finding fish with abnormal fins. Finding an algal mat with an orange-red hue.
finding numerous dead small animals near the lake
The wing of a bat is homologous to the _____ of a whale. tail blowhole flipper baleen rib cage
flipper
Which of the following is regarded as a density-independent factor in the growth of natural populations? emigration intraspecific competition interspecific competition flooding predation
flooding
A diagram of the trophic relationships of a community showing who eats whom is called a(n) __________.
food web
Which of the following are basic components of the Hardy-Weinberg model? Frequencies of two alleles in a gene pool before and after many random matings Allele frequencies in a subset of the population Allele frequencies, phenotype frequencies Allele frequencies, number of individuals in the population
frequencies of two alleles in a gene pool before and after many random matings
A life cycle in which the only multicellular form is haploid is most typical of __________.
fungi
Which term describes the multicellular haploid form of a protist that shows alternation of generations?
gametophyte
Which of the following genetic processes may be most helpful in accounting for the Cambrian explosion? binary fission chromosomal condensation random segregation gene duplication
gene duplication
The Neanderthal DNA discovered in Homo sapiens is best explained by ____.
gene flow
The ease with which humans travel across the globe is likely to increase _____.
gene flow
Allelic variation is an important source of __________ in a population. genetic diversity clonal diversity asexual reproduction mitosis None of the listed responses is correct.
genetic diversity
Allele frequencies in a gene pool may shift randomly and by chance. What is this random shift called?
genetic drift
Modern travel along with migration reduces the probability of _____ having an effect on the evolution of humans.
genetic drift
Suppose that a few individuals of a lizard species are transported on a log that floats from the mainland, where the lizard is abundant, to a distant island, where prior to this event no lizards (of any species) existed. The environmental conditions on the island are similar to those on the mainland. A small population of this lizard becomes established on the island; within a few years, allele frequencies in the island population differ greatly from those in mainland populations. Which of the following is the most likely cause of the genetic differences between the island and mainland populations? mutation gene flow genetic drift natural selection
genetic drift
Which factor does not affect a habitat's carrying capacity? Number of nesting sites Genetic variation in the population Availability of food Intensity of predation
genetic variation in the population
At the time Darwin voyaged on the HMS Beagle, the popularly accepted theory in Western culture that explained the origin of Earth's plants and animals held that the various species __________.
had been created by divine intervention a few thousand years before
Evidence of which structure or characteristic would be most surprising to find among fossils of the Ediacaran fauna? embryos true tissues bilateral symmetry hard parts
hard parts
One hypothesis suggests that the Cambrian explosion was caused by the rise of predator-prey relationships. This hypothesis is best supported by an increased incidence of which of the following fossil traces? worm burrows hard parts larger animals organic material
hard parts
What do you observe about the relative timing of the peaks in lynx numbers and hare numbers? What might explain the observation that hare numbers typically peaked slightly before lynx numbers?
hare numbers typically peaked slightly before hare numbers the lynx depend on the hares for food, but there is a delay between increased food availability and increased reproduction by the lynx
As climate changes because of global warming, plant species' ranges in the northern hemisphere may move northward. The trees that are most likely to avoid extinction in such an environment are those that ________.
have larger, more contiguous established populations to begin with
A particular species of protist has obtained a chloroplast via secondary endosymbiosis. You know this because the chloroplasts _____.
have three or four membranes
Which term describes the ability of a trait to be passed on to offspring? Heritability Fitness Adaptation Evolution
heritability
Which of the following is the most inclusive term for an organism that obtains organic food material by eating other organisms or substances derived from them? heterotroph autotroph decomposer producer
heterotroph
Natural selection involves energetic trade-offs between _____. choosing how many offspring to produce over the course of a lifetime and how long to live producing large numbers of gametes when employing internal fertilization versus fewer numbers of gametes when employing external fertilization high survival rates of offspring and the cost of parental care increasing the number of individuals produced during each reproductive episode and a corresponding decrease in parental care
high survival rates of offspring and the cost of parental care
The primates that spend the most time walking upright are the _____. apes prosimians New World monkeys hominids Old World monkeys
hominids
If one organ is an exaptation of another organ, then these two organs _____.
homologous
On an evolutionary tree, __________. homologous characteristics form a nested pattern organisms that are positioned close to each other are closely related scientists are sure of the correct placement and relationships of all organisms the concept of descent with modification is not well-represented None of the listed responses is correct
homologous characteristics form a nested pattern
Which of the following occurs in meiosis, but not mitosis? Homologous chromosomes separate. The cells formed have the same combination of genes as found in the initial cell. The nuclear envelope disappears. Sister chromatids undergo disjunction. A spindle apparatus forms.
homologous chromosomes separate
Why is a pathogen generally more virulent in a new habitat?
hosts in new environments have not had a chance to become resistant to the pathogen through natural selection
Which of the following would seem to be an example of neutral variation? Human fingerprints Homozygosity of the cheetah population Polymorphism of the Galápagos finches Founder effect Moth coloration
human fingerprints
With which of the following statements would a biologist be most inclined to agree? Humans represent the pinnacle of evolution and have escaped from being affected by natural selection. Humans and other apes represent divergent lines of evolution from a common ancestor. Humans evolved from chimpanzees. Humans and other apes are the result of disruptive selection in a species of chimpanzee.
humans and other apes represent divergent lines of evolution from a common ancestor
Which of the following statements about a population experiencing logistic growth is true? If the K and N values are far apart, the population will grow very slowly. If N is less than K, the population will not grow. If the K and N values are similar, the amount of available resources is high. If N is greater than K, the population will shrink.
if N is greater than K, the population will shrink
Select the correct statement about the factors that limit the growth of a population. The most important factor limiting population growth is the scarcest factor in that area. Density-dependent factors are biotic; density-independent factors are abiotic. If a factor limits population growth, increasing its availability will increase population growth.
if a factor limits population growth, increasing its availability will increase population growth
The difference between immigration and emigration is that _________.
immigration is the influx of new individuals from other areas whereas emirgration is the movement of individuals out of a population
The existence of evolutionary trends, such as increasing body sizes among horse species, is evidence that _____.
in particular environments, similar adaptations can be beneficial to more than one species
A species of malaria-carrying mosquito lives in a forest in which two species of monkeys, A and B, coexist. Species A is immune to malaria, but species B is not. The malaria-carrying mosquito is the chief food for a particular kind of bird in the forest. If all these birds were suddenly eliminated by hunters, which of the following would be an immediately observable consequence? Increased mortality in monkey species B Increased mortality (death rate) in monkey species A Increased mortality in the malaria-carrying mosquitoes Emergence of malaria-resistant strains in monkey species B Emergence of malaria-sensitive strains in monkey species A
increased mortality in monkey species B
Which of the following is thought to be a possible consequence of rising CO2 levels? Increased vegetative productivity C3 crops, such as wheat and soybeans being replaced by more C4 plants such as corn Falling global temperature Increased breakdown of atmospheric ozone More rapid warming at the equator than at the poles
increased vegetative productivity
As a population approaches carrying capacity, environmental resistance __________.
increases
Which statement below describes a finding of researchers who studied the decline of red-cockaded woodpeckers? Individuals generally have a better chance of reproducing by remaining behind than by dispersing and excavating homes in new territories. The population decline could be traced to periodic brush fires. The woodpeckers live in groups of one breeding pair and up to four sterile "helpers" that help incubate eggs and feed nestlings. The birds would not occupy nesting cavities created by the researchers. Red-cockaded woodpeckers drill small holes around their nest cavities. The resin that accumulates around the holes attracts small insects for the nestlings to eat.
individuals generally have a better chance of reproducing by remaining behind than by dispersing and excavating homes in new territories
Adaptations are defined as __________.
inherited characteristics of organisms that enhance their survival and reproduction in specific environments
In a particular case of secondary succession, three species of wild grass all invaded a field. By the second season, a single species dominated the field and the other two species had a lower relative abundance. A possible factor contributing to the abundances of these species in this example of secondary succession is ________. parasitism equilibrium immigration inhibition
inhibition
Which of the following would be most difficult to manage under the federal Clean Water Act? Insecticide runoff from a neighborhood. Water pollution from a paper mill. Coal ash from a coal-fired power plant. Effluent from a wastewater treatment plant.
insecticide runoff from a neighborhood
Which of the following is not an observation or inference that Darwin made while developing his theory of evolution? Interactions between individuals and their environments cause individuals to evolve. Members of a population often vary in their inherited traits. Individuals whose inherited traits give them a higher probability of surviving and reproducing in a given environment tend to leave more offspring than do other individuals. All species can produce more offspring than their environments can support, and many of these offspring fail to survive and reproduce. The unequal abilities of individuals to survive and reproduce will lead to the accumulation of favorable traits in the population over generations.
interactions between individuals and their environments cause individuals to evolve
During _____ the cell grows and replicates both its organelles and its chromosomes.
interphase
Nucleoli are present during _____.
interphase
The relationship between an organism and individuals of other species in a community involves _________. interspecific interactions an ecological niche an ecological footprint carrying capacity of the area a demographic transition
interspecific interactions
An exotic species is a(n) _________.
introduced species
Which of the following statements is a likely explanation for why invasive species take over communities into which they have been introduced? Invasive species have a higher reproductive potential than native species. Invasive species are not held in check by the predators and agents of disease that have always been in place for native species. Invasive species come from geographically isolated regions, so when they are introduced to regions where there is more competition, they thrive. Invasive species are less efficient than native species in competing for the limited resources of the environment.
invasive species are not held in check by the predators and agents of disease that have always been in place for native species
Ignoring migration, the age structure of a human population likely to decrease in size will have what shape? a rectangle tapering toward the top inverted pyramid Both an inverted pyramid and a rectangle tapering toward the top result in a population that decreases in size. pyramid Both a pyramid and a rectangle tapering toward the top result in a population that decreases in size.
inverted pyramid in such a population the majority of individuals are in their postreproductive years. such a population is expected to decrease
Characteristic of the bdelloid rotifer is that it __________.
is an example of an animal that has not reproduced sexually in 40 mil. years
Character displacement differs from resource partitioning because character displacement ________.
is directly linked to the evolution of genotypes that have allowed alternate resource use
The rosy periwinkle from Madagascar is important because _________.
it contains alkaloids that inhibit cancer cell growth
The average age of childbearing in country A is 26, whereas the average age in country B is 30. In each country, the average number of offspring per woman is 3. Which of the following statements about the population growth rate in each country must be true? The population growth rate in country A is lower than in country B. It is not possible to compare the population growth rates of countries A and B. The population growth rates in countries A and B are the same. The population growth rate in country A is higher than in country B.
it is not possible to compare the population growth rates of countries A and B this is because the death rates in each country are unknown
On the back of your skull you can feel a small bump, below which is an opening where the spinal cord enters the skull. The location of this opening toward the bottom of the skull is significant in evolutionary biology for what reason?
it occurred as a result of the change to a bipedal stance
The major contribution of sex to evolution is that __________.
it provides a method to increase genetic variation
A dog gives birth to three puppies one year. Three years later, she gives birth to six puppies. Which type of life history pattern is characteristic of this organism? Iteroparity Semelparity Exponential population growth Big-bang reproduction r-selection
iteroparity
__________ is reproduction where adults produce offspring over many years.
iteroparity
Which pair of terms most accurately describes life history traits for a stable population of wolves? semelparous; r-selected iteroparous; r-selected semelparous; K-selected iteroparous; K-selected
iteroparous; k-selected
Which pair of chickens should a farmer breed to produce larger chickens? Small hen, small rooster Large hen, small rooster Small hen, large rooster Large hen, large rooster
large hen, large rooster
A newly mated queen ant founds a nest in an unoccupied patch of suitable habitat. Assuming that no disasters strike the nest, which of the following types of equations is likely to best describe the population growth of the new colony?
logistic
A graduate student finds an organism in a pond and thinks it is a freshwater sponge. A postdoctoral student thinks it looks more like an aquatic fungus. How can they decide whether it is an animal or a fungus?
look for cell walls under a microscope
Sexual recombination includes the shuffling of chromosomes in __________ and fertilization.
meiosis
The process called __________ reduces the chromosome number by __________.
meiosis; two consecutive cell divisions
Which of the following is found in eukaryotic cells but not in prokaryotic cells? membrane-enclosed organelles plasma membrane cell wall DNA
membrane-enclosed organelles
Homologous pairs of chromosomes are lined up independently of other such pairs during _____.
metaphase I
Generation-to-generation change in the allele frequencies in a population is _____.
microevolution
Mark Shaffer, of Duke University, studied grizzly bears in Yellowstone National Park to determine this threatened species' _________.
minimal viable population
Based on the intermediate disturbance hypothesis, a community's species diversity is increased by ________.
moderate levels of disturbance
Which of these anthropoid groups consists of primates who are mostly tree dwellers and whose forelimbs and hind limbs are about equal in length? monkeys hominids prosimians primates apes
monkeys
Connections between habitat fragments are referred to as __________.
movement corridors
The poison-arrow frogs Dendrobates of tropical America are all brightly colored and have very similar patterns. Although each species is distasteful to predators and all possess toxic skin secretions, some of the species live quite separate from the others. The adaptive relationship among these species is best termed __________. Müllerian mimicry cryptic coloration parasitism commensalism Batesian mimicry
mullerian mimicry
Which of the following can form entirely new alleles? Mutation Natural selection Genetic drift Sexual recombination The environment
mutation
Which life cycle stage is found in plants but not animals? Multicellular haploid Gamete Zygote Multicellular diploid Unicellular diploid
mutlicellular haploid
Certain species of acacia trees in Central and South America have hollow thorns that house stinging ants, which attack anything that touches the tree. The ants feed on nutrients produced by the acacias. This is an example of __________.
mutualism
All of the following conditions are required for Hardy-Weinberg equilibrium except __________. natural selection a large population no mutation no gene flow random mating
natural selection
Darwin's explanation of how adaptations arise centered on __________. natural selection inheritance of acquired characteristics use and disuse artificial selection descent with modification
natural selection
In Darwin's view of descent with modification, __________. natural selection can improve the match between an organism and its environment an organism's traits only affect its own survival individuals can evolve environmental changes have no effect on the organisms living in that environment natural selection only operates when an organism needs to evolve
natural selection can improve the match between an organism and its environment
Resource competition, territoriality, disease, and toxic wastes are some of the factors that provide _____ and help regulate population. positive feedback zero population growth population dynamics metapopulations negative feedback
negative feedback as populations grow, these factors may act to increase mortality or slow reproduction, thus slowing population growth
Which of the following is (are) unique to animals? flagellated gametes heterotrophy nervous system signal conduction and muscular movement the structural carbohydrate, chitin
nervous system signal conduction and muscular movement
Point mutations in noncoding regions of DNA result in __________.
neutral variation
Which of these primate groups lives in trees in Central and South America and have nostrils that are wide open and far apart? hominids apes New World monkeys anthropoids Old World monkeys
new world monkeys
Denitrifying bacteria convert _____ to _____.
nitrates, nitrogen gas
_____ removes nitrogen from the atmosphere.
nitrogen fixation
A man who is a dwarf with achondroplasia and normal vision marries a color-blind woman of normal height. The man's father was six feet tall, and both the woman's parents were of average height. Dwarfism caused by achondroplasia is autosomal dominant, and red-green color blindness is X-linked recessive. How many of their daughters might be expected to be color-blind with achondroplasia?
none
Crossing over, resulting in an increase in genetic variation, occurs between _____.
nonsister chromatids of homologous chromosomes
In meiosis, __________ of __________ cross over and form __________.
nonsister chromatids; homologous pairs; chiasmata
Biogeochemical cycles are crucial to ecosystem function because _____.
nutrients and other life-sustaining molecules are in limited supply and must be continually recycled
How might an ecologist test whether a species is occupying all of its fundamental niche or only a portion of it?
observe if the species expands its range after the removal of a competitor
Which of the following traits is characteristic of K-selected populations? offspring with good chances of survival small offspring many offspring per reproductive episode a high intrinsic rate of increase
offspring with good chances of survival
Genes for the resistance of antibiotics are usually located __________.
on plasmids
How can biodiversity affect the way we decontaminate industrial sites? I) Bacteria have been found to be able to detoxify certain chemicals; perhaps there are more. II) Trees produce sawdust, which can be used to soak up chemicals. III) Species evolving in contaminated areas could adapt and detoxify the area.
only I
Which statements about K are correct? I) K varies among populations. II) K varies in space. III) K varies in time. IV) K is constant for any given species.
only I, II, and III
What insight did Darwin gain from reading Thomas Malthus's essay on human suffering?
organisms have the capacity to over reproduce
Bagworm moth caterpillars feed on evergreens and carry a silken case or bag around with them in which they eventually pupate. Adult female bagworm moths are larval in appearance; they lack the wings and other structures of the adult male and instead retain the appearance of a caterpillar even though they are sexually mature and can lay eggs within the bag. This is a good example of _____.
paedomorphosis
Which of the following studies would shed light on the mechanism of spread of H5N1 virus from Asia to North America? Perform cloacal or saliva smears of migrating waterfowl to monitor whether any infected birds show up in Alaska. Test fecal samples for H5N1 in Asian waterfowl that live near domestic poultry farms in Asia. Test for the presence of H5N1 in poultry used for human consumption worldwide. Locate and destroy birds infected with H5N1 in Asian open-air poultry markets.
perform cloacal or saliva smears of migrating waterfowl to monitor whether any infected birds show up in Alaska
The duplication of homeotic (Hox) genes has been significant in the evolution of animals because it _____.
permitted the evolution of novel forms
Which of the following types of organisms is an example of a producer? phytoplankton zooplankton decomposer herbivore
phytoplankton
The order of the stages of primary succession beginning with glacial retreat as seen at Glacier Bay, Alaska, are ________.
pioneer, dryas, alder, and spruce stages
Which of the following is not an observation or inference on which natural selection is based? Poorly adapted individuals never produce offspring. There is heritable variation among individuals. Species produce more offspring than the environment can support. Individuals whose characteristics are best suited to the environment generally leave more offspring than those whose characteristics are less well suited. Only a fraction of an individual's offspring may survive.
poorly adapted individuals never produce offspring
A group of individuals of a single species living in the same general area is called a _________. population community family clade taxon
population
A(n) __________ is the smallest unit that can evolve. population individual species community adaptation
population
Fluctuations in the numbers of individuals in a population from year to year are called _________.
population dynamics
A community is best described as the collection of
populations of different species that live in a particular area
Examples of defensive adaptations include all of the following except ________. predation mechanical defense aposematic coloration Batesian mimicry Müllerian mimicry
predation
Which of the following factors most likely contributed to the extinction of many Ediacaran life forms? loss of habitat due to increased temperatures, poisoning from high oxygen levels, and loss of developmental flexibility predation by new species, poisoning from high oxygen levels, and loss of habitat due to increased temperatures predation by new species, faster movement by new species, and increased developmental flexibility by new species predation by new species, poisoning from high carbon dioxide levels, and loss of developmental flexibility
predation by new species, faster movement by new species, and increased development flexibility by new species
Which of the following statements about age pyramids is true? Age distribution in less-developed countries is bottom-heavy, indicating that these populations are dominated by the very old. Populations in developed countries grow more quickly than populations in less-developed countries. Age distribution in developed countries shows an hourglass pattern, with the greatest numbers of people being either very young or very old. Predictions of a population's future take into account such factors as increasing survivorship and fecundity levels that remain the same.
predictions of a population's future take into account such factors as increasing survivorship and fecundity levels that remain the same
A cow eating grass is an example of a _____.
primary consumer by feeding on a producer, the cow is acting as a primary consumer
Gastrulation is the process that directly forms the _____.
primary germ layers
Arrange the following taxonomic terms in order from most inclusive (most general) to least inclusive (most specific). primates, anthropoids, apes, hominins, Homo primates, hominins, apes, anthropoids, Homo primates, apes, anthropoids, hominins, Homo primates, anthropoids, hominins, Homo
primates, anthropoids, apes, hominins, Homo
In an ecosystem, phytoplankton are _____.
producers (autotrophs)
To recycle nutrients, an ecosystem must have, at a minimum, _____.
producers and decomposers
In an area where soil has not yet formed, called primary succession, the life-forms that are first found are _________.
prokaryotes and protists
Spindle fibers attach to kinetochores during _____.
prometaphase
Chromosomes become visible during _____.
prophase
_____ are the oldest known primate group.
prosimians
Ignoring migration, the age structure of a human population likely to increase in size will have what shape? Both an inverted pyramid and a rectangle tapering toward the top result in a population that increases in size. a rectangle tapering toward the top pyramid Both a pyramid and a rectangle tapering toward the top result in a population that increases in size. inverted pyramid
pyramid this would mean that most individuals are in the prereproductive years. such a population is expected to increase
Life history traits that are favored in uncrowded environments are known as _________. r-selection K-selection v-selection iteroparity semelparity
r-selection
Which of the following sets of conditions is required for Hardy-Weinberg equilibrium?
random mating, no natural selection, and a large population
A lake community with four trophic levels suddenly suffers from algal blooms. Using the strategy of biomanipulation, an ecologist may propose __________. removing fish that eat zooplankton removing zooplankton adding mineral nutrients to the water adding fish that eat zooplankton removing the fourth trophic level in the lake
removing fish that eat zooplankton
In contrast to bioremediation, which is a strategy for _____, biological augmentation _____ a degraded ecosystem.
removing harmful substances; uses organisms to add essential materials to
Which of these traits is most strongly associated with the adoption of bipedalism? repositioning of foramen magnum enhanced depth perception shortened hind limbs opposable big toe
repositioning of foramen magnum
Similar species can coexist in a community by using _________. resource partitioning competitive exclusion a demographic transition predation character displacement
resource partitioning
Consider this segment of a food web: Snails and grasshoppers eat pepper plants; spiders eat grasshoppers; shrews eat snails and spiders; owls eat shrews. The shrew occupies the trophic level(s) of _____.
secondary and tertiary consumers
When a human eats a steak, the human is acting as a _____.
secondary consumer by feeding on a primary consumer, the human is acting as a secondary consumer
Which area is not one of the three major reservoirs of the global carbon cycle Sedimentary rock. Terrestrial ecosystems. Oceans. Atmosphere.
sedimentary rock
_________ describes an organism that reproduces once in its lifetime. Semelparity Iteroparity K-selection r-selection v-selection
semelparity
The evolution of animal species has been prolific (current estimates of species numbers reach into the tens of millions). Much of this diversity is a result of the evolution of novel ways to ________.
sense, feed, and move
Which of the following statements about hominin evolution is correct? As hominins have evolved, _____. sexual dimorphism was significantly reduced they have developed longer fingers canine teeth have increased in size the foramen magnum has shifted farther back on the skull jaw size has increased
sexual dimorphism was significantly reduced
Genetic diversity requires __________.
sexual reproduction independent assortment crossing over between nonsister chromatids of homologous chromosomes random fertilization
Which term describes the fusion of two gametes to form a diploid zygote?
synagmy
Cytokinesis often, but not always, accompanies _____.
telophase
Which statement below is true about sexual selection? Sexual selection can result in sexual dimorphism—marked differences between the sexes in secondary sexual characteristics that are not associated directly with reproduction. Intrasexual selection leads to the death of most unfit males in combat. Showy secondary sexual characteristics cannot be explained because they break all of the rules of natural selection. In most vertebrates, females court the males. There is no evidence that intrasexual selection takes place between females.
sexual selection can result in sexual dimorphism = marked differences between the sexes in secondary sexual characteristics that are not associated directly with reproduction
_________ is used to compare the diversity of communities across time and space.
shannon diversity
The mark-recapture method would be best for sampling a population of _____. sharks oysters rose bushes maple trees wheat
sharks works best for active species whose individuals tend to be highly mobile
Which of the following characteristics occur in Homo naledi? large brain, feet that allowed bipedal walking, hands able to manipulate small objects large brain, feet that allowed occasional erect posture, hands able to manipulate small objects small brain, feet that allowed bipedal walking, hands able to swing from branch to branch small brain, feet that allowed bipedal walking, hands able to manipulate small objects
small brain, feet that allowed bipedal walking, hands able to manipulate small objects
Which of the following is a correct statement about MacArthur and Wilson's island equilibrium model? Islands closer to the mainland have higher extinction rates. As the number of species on an island increases, the emigration rate decreases. Small islands receive few new immigrant species. Competitive exclusion is less likely on an island that has large numbers of species.
small islands receive few new immigrant species
The potential evapotranspiration is determined by __________.
solar radiation
The main reason polar regions are cooler than the equator is that ________.
solar radiation strikes the poles at a lower angle and travels through more atmosphere
Generalized global air circulation and precipitation patterns are caused by ________.
solar radiation that warms most air masses near the equator, which then cool and release precipitation as they rise, and then, at high altitude, move north or south of the tropics and sink back to the surface as dry air masses
The bacteria Staphylococcus aureus has developed resistance to some antibiotic drugs. How did this resistance come about?
some members of the bacteria populations possessed some sort of genetic variation for antibiotic resistance that was selected for when the bacteria was exposed to the drugs
In 1959, doctors began using the powerful antibiotic methicillin to treat infections of Staphylococcus aureus, but within two years, methicillin-resistant strains of S. aureus (MRSA) appeared. How did the resistant strains of S. aureus emerge? Staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other individuals. Over time, these resistant individuals became increasingly common. In response to treatment of Staphylococcus aureus infections with methicillin, some bacteria began to synthesize cell walls using a protein that was not affected by methicillin. These bacteria survived the methicillin treatments and reproduced at higher rates than did other individuals. Over time, these resistant individuals became increasingly common. In response to treatment of Staphylococcus aureus infections with methicillin, bacterial populations gradually began to synthesize cell walls using a protein that was not affected by methicillin.
staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other inviduals. over time, these resistant individuals became increasingly common
Which trophic level is most vulnerable to extinction? primary consumer level producer level tertiary consumer level secondary consumer level
tertiary consumer level
A mutualism is an ecological relationship between two species
that both benefit from the relationship
An example of investing in ecosystem services is _________. the $1 billion that New York City invested to buy land and restore the Catskill Mountains the $8 billion that New York City invested to buy land and restore the Catskill Mountains the $8 billion that New York City spent to build a new water treatment plant the $300 million that New York City spends each year on its water treatment plant and on job creation
the 1 billion that NYC invested to buy land and restore the catskill mountains
Soapberry bugs use needlelike "beaks" to feed on seeds within the fruits of various plants. Bugs feed most successfully when their beak length matches the size of the fruit on which they are feeding. For 25 years, populations of soapberry bugs in central Florida have been feeding on small goldenrain tree fruits that were introduced to the area, rather than on the larger native balloon vine fruits that serve as food for other soapberry bug populations. Beak lengths of soapberry bugs are variable, but the average beak length is shorter in soapberry bug populations that feed on goldenrain tree fruits than in populations that feed on balloon vine fruits, as shown in the graph. How does natural selection act on beak length in soapberry bug populations?
the action of natural selection on beak length in soapberry bug populations varies with the environment
Which of these was the first of the major events that stimulated an increase in the size of the human population? the discovery of vaccines the advent of agriculture the bubonic plague the discovery of antibiotics the Industrial Revolution
the advent of agriculture
Carolus Linnaeus is considered to be the founder of __________, and he __________.
the binomial classification system; thought that resemblances among different species reflected the pattern of their creation
When a scientist describes the "body plan" of a phylum, he or she is implying that ________.
the body shapes we see now have been more successful than other in the past
A hurricane hits a small island, killing all but a few members of a bird population. This is an example of __________.
the bottleneck effect
No population can grow indefinitely. The ultimate size of any population is limited by __________.
the carrying capacity of its environment
What does each branch point on an evolutionary tree represent?
the common ancestor of the lineages beginning there and to the right of it
In the United States today, about half of the corn crop is genetically engineered with a protein that is toxic to corn borers, an insect pest of corn. Which of the following conditions would be necessary for evolution of resistance to the toxic protein to occur in the corn borer? The corn borer must lack variation in resistance to the toxic protein. The corn borer must have or generate (by mutation) heritable variation in resistance to the toxic protein. The resistant corn borers must survive better or reproduce more than nonresistant corn borers. The corn borers must experience no success in their ability to survive or reproduce. The corn borers must experience unlimited success in their ability to survive or reproduce.
the corn borer must have or generate (by mutation) heritable variation in resistance to the toxic protein. the resistant corn borers must survive better or reproduce more than nonresistant corn borers
In the figure, imagine a different scenario where the death rate per capita was dependent upon (and positively correlated with) the density of the population, and the birth rate was instead density independent. As the density of the population increased, ________. the death rate would remain stable and the birth rate would increase the death rate would decrease and the birth rate would decrease the death rate would increase and the birth rate would decrease the death rate would increase and the birth rate would remain stable
the death rate would increase and the birth rate would remain stable
Which of these was the third of the major events that stimulated an increase in the size of the human population?
the discovery of vaccines and the discovery of antibiotics
Although there are organisms whose life histories fall somewhere between iteroparity and semelparity, life history always represents a trade-off. Why is this?
the energy cost of reproduction is high, so there are not enough resources to reproduce often, produce many offspring, and take care of them
According to the endosymbiotic theory, why was it adaptive for the larger (host) cell to keep the engulfed cell alive, rather than digesting it as food?
the engulfed cell provided the host cell with ATP
The destruction of the ozone layer is most directly linked to __________.
the release of CFCs into the atmosphere
Suppose conjugation occurs between an Hfr cell and an F- cell. Although not typical, what would have to occur for the recipient cell to become an Hfr cell?
the entire F factor would have to be incorporated into the recipient cell's chromosome
In the Hardy-Weinberg equation, 2pq represents __________.
the expected frequency of the heterozygous genotype
In the Hardy-Weinberg equation, q2 represents __________.
the expected frequency of the homozygous recessive genotype
Which of the following is an accurate statement regarding human evolution? The first humans evolved in Africa. In the latest phase of human evolution, there has been a greater reliance on culture. Once bipedality, tool use, and larger brains evolved in humans, humans stopped evolving. The fossil record contains creatures with features that are intermediate between those of modern humans and quadrupedal apes.
the first humans evolved in Africa in the latest phase of human evolution, there has been a greater reliance on culture the fossil record contains creatures with features that are intermediate between those of modern humans and quadrupedal apes
A storm separates a small number of birds in a migrating population. These birds end up at a destination different from where they usually migrate and establish a new population in this new area. This is an example of __________.
the founder effect
Which of the following is true? The genus Homo and the genus Australopithicus co-evolved. The genus Homo evolved into the genus Australopithicus. The genus Australopithicus evolved into the genus Homo. The genus Homo and the genus Australopithicus contain the same species.
the genus autralopithicus evolved into the genus homo
A female fly, full of fertilized eggs, is swept by high winds to an island far out to sea. She is the first fly to arrive on this island and the only fly to arrive in this way. Thousands of years later, her numerous offspring occupy the island, but none of them resembles her. There are, instead, several species, each of which eats only a certain type of food. None of the species can fly and their balancing organs (halteres) are now used in courtship displays. The male members of each species bear modified halteres that are unique in appearance to their species. Females bear vestigial halteres. The ranges of all of the daughter species overlap. Which of these fly organs, as they exist in the description, best illustrates an exaptation?
the halteres
The sickle-cell allele, which is recessive, causes anemia but confers resistance to malaria in individuals who possess it. However, homozygous recessive individuals often die from anemia but not from malaria, and homozygous dominant individuals do not have anemia but could die from malaria. Heterozygous individuals have the highest relative fitness. This is an example of __________.
the heterozygote advantage
Which of the following statements best describes the trend in the species versus island area data? The increase in number of species with increasing land area slows for larger islands, suggesting that there may be a maximum number of species an island can hold regardless of size. There is no detectable influence of island size on number of species. The number of species on an island increases by roughly 30 for every 5000-square-mile increase in land area. There is a decreasing trend in species number as island size increases.
the increase in number of species with increasing land area slows for larger islands, suggesting that there may be a maximum number of species an island can hold regardless of size
Which of these was the second of the major events that stimulated an increase in the size of the human population?
the industrial revolution
When interspecific competition has an outcome called competitive exclusion, _________.
the inferior competitor will be eliminated
At what time of year is the intensity of solar radiation striking each of Earth's hemispheres weakest?
the intensity of solar radiation is weakest in the southern hemisphere in june and in the northern hemisphere in december
According to MacArthur and Wilson's hypothesis of island biogeography, species immigration and extinction rates on a particular island correlate to __________. when the island formed the number of other islands in the archipelago the island's stage of ecological succession the island's size and distance from the mainland how the island formed
the island's size and distance from the mainland
Why has the kingdom Protista been abandoned?
the kingdom protista is not monophyletic some protists are more closely related to plants, animals, or fungi than they are to other protists
Select the correct statement(s) about the transfer of food energy up the trophic levels from its source in autotrophs. An organism feeds at only one trophic level. The length of a food chain is limited by the inefficiency of energy transfer along the chain. Few plants have adaptations to reduce feeding by herbivores.
the length of a food chain is limited by the inefficiency of energy transfer along the chain
During _____ both the contents of the nucleus and the cytoplasm are divided.
the mitotic phase
The oak tree fungal pathogen, Phytophthora ramorum, has migrated 800 kilometers in 15 years. West Nile virus spread from New York State to 46 other states in 5 years. The difference in the rate of spread is probably related to ________. the mobility of their hosts the fact that viruses are very small innate resistance the lethality of each pathogen
the mobility of their hosts
Which of the following is a feature of the "tube-within-a-tube" body plan in most animal phyla?
the mouth and anus form the ends of the inner tube
Which statement regarding the June solstice is true?
the northern hemisphere is tilted toward the sun
Imagine a chain of islands of the same size that are at increasing distances from a mainland. The immigration rate should be highest for islands close to the mainland because they should receive the most colonizers. The extinction rate should be the same for all these islands. Use the equilibrium model of island biogeography to predict how the number of species on an island changes with distance from a mainland. Select the statement below that best represents your prediction. The number of species increases with distance from the mainland. The number of species decreases with distance from the mainland. Immigration and extinction rates balance out so that there is no change in species number with distance from the mainland. The number of species increases as island size increases.
the number of species decreases with distance from the mainland
What happens to the number of species in a community as the area of that community increases?
the number of species in the community increases
In 1970, the average age of childbearing was 28, and the average number of offspring per woman was 3 in a certain country. In 1980, the average age of childbearing was still 28, but the average number of offspring per woman was 2 in that country. If the death rate in the country remained constant during those years, how did the population growth rate change from 1970 to 1980? It is not possible to determine the population growth rate. The population growth rate decreased. The population growth rate increased. The population growth rate stayed the same.
the population growth rate decreased reducing the average number of offspring per woman decreases the population growth rate
Which of the following statements are true of a population at carrying capacity? The population growth rate equals zero. The population continues to grow at a constant rate. The birth rate equals the death rate. The rate at which resources are used is equal to the rate at which they are supplied.
the population growth rate equals zero the birth rate equals the death rate the rate at which resources are used is equal to the rate at which they are supplied
As N approaches K for a certain population, which of the following outcomes is predicted by the logistic equation? The population size will increase exponentially. The carrying capacity of the environment will increase. The population growth rate will not change. The population growth rate will approach zero.
the population growth rate will approach zero
What do all deuterostomes have in common?
the pore (blastopore) formed during gastrulation becomes the anus
What is a locus?
the precise location of a gene on a chromosome
Which of the following observations about flagella is accurate and is consistent with the scientific conclusion that the flagella from eukaryotes and bacteria evolved independently? The protein structure and the mechanism of movement in eukaryotes flagella are different from those of bacteria flagella. The mechanics of movement and protein structure are the same in these flagella, but there are significant genetic differences. The flagella of both eukaryotes and bacteria are made of the same protein, but the configuration is different. Although the mechanism of movement in both flagella is the same, the protein that accomplishes the movement is different.
the protein structure and the mechanism of movement in eukaryotes flagella are different from those of bacteria flagella
When equilibrium is reached on an island, __________. the rate of species immigration will equal the rate of species extinction the number of organisms does not change ecological disturbance is minimized the food web will be highly stable extinction will cease
the rate of species immigration will equal the rate of species extinction
What usually happens to the recipient cell following conjugation with an Hfr cell?
the recipient cell remains an F- cell
No two people are genetically identical, except for identical twins. The main source of genetic variation among human individuals is __________.
the reshuffling of alleles in sexual reproduction
Genetic drift is a process based on _____.
the role of chance
Mechanisms of density-dependent selection includes all of the following except _______.
the size of the brood
The energy for nearly every organism in nearly every ecosystem ultimately comes from _____. minerals in the soil the sun heat from Earth respiration decomposition
the sun
Which statement correctly describes the role of chance in evolution? Evolution by natural selection proceeds by an accumulation of changes that occur by chance. An allele that increases evolutionary fitness cannot be lost from a population by chance events. The ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism's DNA.
the ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism's DNA
Which of the following statements about human evolution is correct? Modern humans are the only human species to have evolved on Earth. The upright posture and enlarged brain of humans evolved separately. Human ancestors were virtually identical to extant chimpanzees. Human evolution has occurred within an unbranched lineage.
the upright posture and enlarged brain of humans evolved separately
In the region of the Rocky Mountains, imagine that one local variety of Ponderosa pine (Pinus ponderosa) predominantly occurs between 5,000-8,500 feet in elevation, where it can best tolerate temperatures and precipitation. If future climate change in this region causes the temperature to increase and rainfall to decrease, then which of the following changes might an ecologist predict about the variety's range?
the variety will occur at higher elevations and/or higher latitudes
What advantage do organisms that reproduce sexually have over organisms that reproduce asexually?
their offspring may be more adaptable to changes in the environment
The success of plants extending their range northward following glacial retreat is primarily determined by ________.
their seed dispersal rate
The technique called polymerase chain reaction (PCR) uses a polymerase from _________.
thermus aquaticus
Loss of "flying foxes" would impact ecosystem diversity because ________.
these bats are important pollinators and seed dispersers in the pacific islands and their loss would harm plant diversity
Long-term studies of Belding's ground squirrels show that immigrants move nearly 2 kilometers from where they are born and become 1%-8% of the males and 0.7%-6% of the females in other populations. On an evolutionary scale, why is this significant? Gradually, the populations of ground squirrels will move from a clumped to a uniform population pattern of dispersion. These immigrants make up for the deaths of individuals, keeping the other populations' size stable. Those individuals that emigrate to these new populations are looking for less crowded conditions with more resources. These immigrants provide a source of genetic diversity for the other populations.
these immigrants provide a source of genetic diversity for the other populations
Which of the following statements about homologous chromosomes is correct? They have genes for the same traits at the same loci. They are found in animal cells but not in plant cells. They pair up in prophase II. They are found in haploid cells. They are found in the cells of human females but not in human males.
they have genes for the same traits at the same loci
Why is it difficult to observe individual chromosomes with a light microscope during interphase?
they have uncoiled to form long, thin strands
Why do some species employ both mitosis and meiosis, whereas other species use only mitosis?
they need both if they are producing plant gametes
How do greenhouse gases contribute to global warming?
they prevent infrared light from leaving earth's atmosphere
Hox genes are thought to play an important role in the development of different morphologies because _____.
they provide positional information in the embryo
Evolution works by _____. constantly increasing complexity molding the environment to conform to the organisms living in it predicting the future "tinkering" with existing structures converging on a particular phenotype
tinkering with existing structures
__________ are the most affected by toxic compounds in the environment because __________. Top-level carnivores; the biomass at any given trophic level is produced from a larger biomass ingested at the level below Cyanobacteria; many of these compounds prevent nitrogen fixation Phytoplankton; many of these compounds halt photosynthesis Primary consumers; they consume primary producers containing the compounds Herbivores; plants tend to store these toxic compounds in large quantities
top level carnivores; the biomass at any given trophic level is produced from a larger biomass ingested at the level below
A zoonotic pathogen is _________.
transferred to humans from other animals
The most ancient branch point in animal phylogeny is the characteristic of having _____.
true tissues or no tissues
Suppose that none of the 44 dolphins encountered in the second sampling had been photographed before. Would you be able to solve the equation for N? What might you conclude about population size in this case?
tthe equation cannot be solved, but you would conclude that the population size is very large
During prophase a homologous pair of chromosomes consists of _____.
two chromosomes and four chromatids
Somatic cells in humans contain __________ set(s) of chromosomes and are therefore termed __________.
two; diploid
At the end of mitosis, __________ daughter cells that are genetically __________ are formed, while at the end of meiosis, __________ daughter cells that are genetically __________ are formed.
two; identical; four; distinct
A survivorship curve that represents high death rates for the young is a ________ curve.
type III
An oak tree produces thousands of acorns, but very few grow into mature oak trees. The oak tree exhibits a __________ survivorship curve.
type III
Jams, jellies, preserves, honey, and other foods with high sugar content hardly ever become contaminated by bacteria, even when the food containers are left open at room temperature. This is because bacteria that encounter such an environment ____.
undergo death as a result of water loss from the cell
Herring gulls fiercely defend the areas around their nests in cliff-top breeding colonies. Within the colony they would show a __________ dispersion pattern.
uniform
The history of hominin evolution demonstrates ________. unrelated traits (that is, characters of skulls and hips/feet) evolve together the increase in rainfall favored the ability to walk upright the decrease in rainfall favored maintaining the ability to climb trees unrelated traits can evolve at different rates
unrelated traits can evolve at different rates
Plants ________ to protect themselves from herbivores.
use chemical toxins
Homologies that appear to have marginal, if any, importance to an organism are called __________.
vestigial structures
What absolutely essential resource is likely to limit the carrying capacity of Earth for humans? Water Oil Raw materials such as metals Space Oxygen
water
Coral reefs occur on the southeast coast of the United States but not at similar latitudes on the southwest coast. Differences in which of the following most likely account for this?
water temperature driven by ocean currents
Termites eat wood, but many do not produce enzymes themselves that will digest the cellulose in the wood. Instead, some termites house a complex community of protozoa, bacteria, and archaea that could help digest the cellulose. Imagine an experiment that fed termites either wood only or wood and antibiotics, and then measured the amount of energy extracted from the wood. If both groups gained equal amounts of energy, which of the conclusions is the most logical?
we would conclude that the bacteria did not contribute to the digestion of cellulose and lignin
Under which of the following circumstances would interspecific competition be most obvious?
when a nonnative organism is introduced to a community
What is the key difference between a dominant species and a keystone species?
while dominant species are the most abundant, keystone species exert control through important roles or niches
Which of the following is the best example of gene flow? Wind blows pollen from one population of plants to another and cross-fertilization occurs. A small population of humans colonizes a newly formed island. Genes are shuffled by the crossing over of chromosomes during meiosis. An earthquake results in the formation of a canyon, splitting a population of toads apart. A fire drastically reduces the size of a white-tailed deer population. The remaining individuals spread out throughout the remaining forest.
wind blows pollen from one population of plants to another and cross-fertilization occurs
Under which of the following conditions would a population most likely experience exponential growth? Habitat with limited resources. Young populations with few individuals. Environment with a low carrying capacity. Large number of individuals in the starting population.
young populations with few individuals this is because they have not used up the supply of resources
Which equation represents the logistic growth rate of a population? ΔN/Δt=rN r=b−d ΔN/Δt=rmaxN(K−N)K ΔN.Δt=rmaxN
ΔN/Δt=rmaxN(K−N)K