Evolution: Final Flashcards
During a study session about evolution, one of your fellow students remarks, “The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result.” Which statement would you use to correct this student’s misconception?
Characteristics acquired during an organism’s life are generally not passed on through genes.
Who was the naturalist who synthesized a concept of natural selection independently of Darwin?
Alfred Wallace
Charles Darwin was the first to propose
a mechanism for evolution that was supported by evidence
In evolutionary terms, the more closely related two different organisms are, the
more recently they shared a common ancestor.
Evolution by natural selection is based on all of the following except
variation exists within populations.
the fittest individuals tend to leave the most offspring.
there is differential reproductive success within populations.
populations tend to produce more individuals than the environment can support.
individuals must adapt to their environment.
individuals must adapt to their environment
Which statement about natural selection is most correct?
Adaptations beneficial in one habitat should generally be beneficial in all other habitats as well.
Different species that together occupy the same habitat will adapt to that habitat by undergoing the same genetic changes.
Adaptations beneficial at one time should generally be beneficial during all other times as well.
Well-adapted individuals leave more offspring, and thus contribute more to the gene pool, than poorly adapted individuals.
Natural selection is the sole means by which populations can change.
Well-adapted individuals leave more offspring, and thus contribute more to the gene pool, than poorly adapted individuals.
To observe natural selection’s effects on a population, what must be true?
One must observe more than one generation of the population.
The population must contain genetic variation.
Members of the population must increase or decrease the use of some portion of their anatomy.
A and C only
A and B only
A and B only
During drought years on the Galapagos, small, easily eaten seeds become rare leaving only large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, then what should one expect to result from natural selection?
Small birds gaining larger beaks by exercising their mouth parts.
Small birds mutating their beak genes with the result that later-generation offspring have larger beaks.
Small birds anticipating the long drought and eating more to gain weight and, consequently, growing larger beaks.
More small-beaked birds dying than the larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.
Larger birds eating less so smaller birds can survive
During drought years on the Galapagos, small, easily eaten seeds become rare leaving only large, hard-cased seeds that only birds with large beaks can eat. If a drought persists for several years, then what should one expect to result from natural selection?
Small birds gaining larger beaks by exercising their mouth parts.
Small birds mutating their beak genes with the result that later-generation offspring have larger beaks.
Small birds anticipating the long drought and eating more to gain weight and, consequently, growing larger beaks.
More small-beaked birds dying than the larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.
Larger birds eating less so smaller birds can survive
More small-beaked birds dying than the larger-beaked birds. The offspring produced in subsequent generations have a higher percentage of birds with large beaks.
Which of the following statements is not an inference of natural selection?
Subsequent generations of a population should have greater proportions of individuals that possess favorable traits.
An individual organism undergoes evolution over the course of its lifetime
Often only a fraction of offspring survive, because there is a struggle for limited resources.
Individuals whose inherited characteristics best fit them to the environment should leave more offspring.
Unequal reproductive success among its members leads a population to adapt over tim
An individual organism undergoes evolution over the course of its lifetime
genetic variation among individuals
variation among individuals caused by environmental factors
sexual reproduction
A and C only
A, B, and C
genetic variation among individuals
A biologist studied a population of squirrels for 15 years. During that time, the population was never fewer than 30 squirrels and never more than 45. Her data showed that over half of the squirrels born did not survive to reproduce, because of competition for food and predation. In a single generation, 90% of the squirrels that were born lived to reproduce, and the population increased to 80. What inferences might you make about this population?
The amount of available food may have increased
The number of predators may have decreased
The squirrel populations in subsequent generations should show greater levels of variation than previous generations because squirrels that would not have survived in the past will now survive
A and B only
A, B, and C
A and B only
Which statement best describes how the evolution of pesticide resistance occurs in a population of insects?
Individual members of the population slowly adapt to the presence of the chemical by striving to meet the new challenge
All insects exposed to the insecticide begin to use a formerly silent gene to make a new enzyme that breaks down the insecticide molecules.
Insects observe the behavior of other insects that survive pesticide application, and adjust their own behaviors to copy those of the survivors.
A number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals.
B and D only
A number of genetically resistant pesticide survivors reproduce. The next generation of insects contains more genes from the survivors than it does from susceptible individuals.
DDT was once considered a “silver bullet” that would permanently eradicate insect pests. Today, instead, DDT is largely useless against many insects. What would need to be true for pest eradication efforts to have been successful in the long run?
Larger doses of DDT should have been applied
All habitats should have received applications of DDT at about the same time
The frequency of DDT application should have been higher.
All individual insects should have possessed genomes that made them susceptible to DDT.
DDT application should have been continual.
All individual insects should have possessed genomes that made them susceptible to DDT.
Structures as different as human arms, bat wings, and dolphin flippers contain many of the same bones, these bones having developed from the same embryonic tissues. How do biologists interpret these similarities?
by identifying the bones as being homologous
by the principle of convergent evolution
by proposing that humans, bats, and dolphins share a common ancestor
A and C only
A, B, and C
A and C only
Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?
Natural selection cannot account for losses, only for innovations.
It can account for these losses by the principle of use and disus
Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits.
These organisms had the misfortune to experience harmful mutations, which caused the loss of these structures.
B and D only
Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits.
t has been observed that organisms on islands are different from, but closely related to, similar forms found on the nearest continent. This is taken as evidence that
island forms and mainland forms descended from common ancestors.
common environments are inhabited by the same organisms.
the islands were originally part of the continent.
the island forms and mainland forms are converging.
island forms and mainland forms have identical gene pools.
island forms and mainland forms descended from common ancestors.
The theory of evolution is most accurately described as
an educated guess about how species originate
one possible explanation, among several scientific alternatives, about how species have come into existence
an opinion that some scientists hold about how living things change over time
an overarching explanation, supported by much evidence, for how populations change over time
an idea about how acquired characteristics are passed on to subsequent generations.
an overarching explanation, supported by much evidence, for how populations change over time
Which of the following is not an observation or inference on which natural selection is based?
There is heritable variation among individuals.
Poorly adapted individuals never produce offspring.
There is a struggle for limited resources, and only a fraction of offspring surviv
Individuals whose characteristics are best suited to the environment generally leave more offspring than those that are less well suite
Organisms interact with their environments.
Poorly adapted individuals never produce offspring.
Within a few weeks of treatment with the drug 3TC, a patient’s HIV population consists entirely of 3TC-resistant viruses. How can this result best be explained?
HIV has the ability to change its surface proteins and resist vaccines.
The patient must have become reinfected with 3TC-resistant viruses.
HIV began making drug-resistant versions of reverse transcriptase in response to the drug.
A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency.
The drug caused the HIV RNA to chang
A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency.
The smallest biological unit that can evolve over time is
a cell.
an individual organism.
a population.
a species.
a population.
A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 36% of the animals display a recessive trait (a), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. What is the most reasonable conclusion that can be drawn from the fact that the frequency of the recessive trait (a) has not changed over time?
The population is undergoing genetic drift.
The two phenotypes are about equally adaptive under laboratory conditions.
The genotype AA is lethal.
There has been a high rate of mutation of allele A to allele
There has been sexual selection favoring allele
The two phenotypes are about equally adaptive under laboratory conditions.
All of the following are criteria for maintaining Hardy-Weinberg equilibrium involving two alleles except
the frequency of all genotypes must be equal.
there should be no natural selection.
matings must be random.
populations must be larg
gene flow from other populations must be zero.
the frequency of all genotypes must be equal.
n a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of the allele a is 0.7. What is the percentage of the population that is homozygous for this allele?
3
9
30
42
49
49
In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of allele a is 0.7. What is the percentage of the population that is heterozygous for this allele?
3
9
21
42
49
42
In a Hardy-Weinberg population with two alleles, A and a, that are in equilibrium, the frequency of allele a is 0.2. What is the frequency of individuals with Aa genotype?
- 20
- 32
- 42
- 80
Genotype frequency cannot be determined from the information provide
0.32
In a population with two alleles, A and a, the frequency of a is 0.50. What would be the frequency of heterozygotes if the population is in Hardy-Weinberg equilibrium?
- 00
- 75
- 50
- 25
- 10
0.50
Most copies of harmful recessive alleles in a sexual species are carried by individuals that are
haploid
polymorphic
homozygous for the allele
heterozygous for the allele
B and C
heterozygous for the allele
In a hypothetical population of 1,000 people, tests of blood-type genes show that 160 have the genotype AA, 480 have the genotype AB, and 360 have the genotype BB. What is the frequency of the A allele?
- 001
- 002
- 100
- 400
- 600
0.400
In a hypothetical population of 1,000 people, tests of blood-type genes show that 160 have the genotype AA, 480 have the genotype AB, and 360 have the genotype BB. What is the frequency of the B allele?
- 001
- 002
- 100
- 400
- 600
0.600
In a hypothetical population of 1,000 people, tests of blood-type genes show that 160 have the genotype AA, 480 have the genotype AB, and 360 have the genotype BB. What percentage of the population has type O blood?
0
10
24
48
60
0
In a hypothetical population of 1,000 people, tests of blood-type genes show that 160 have the genotype AA, 480 have the genotype AB, and 360 have the genotype BB. If there are 4,000 children born to this generation, how many would be expected to have AB blood under the conditions of Hardy-Weinberg equilibrium?
100
960
1,920
2,000
2,400
1,920
In peas, a gene controls flower color such that R = purple and r = white. In an isolated pea patch, there are 36 purple flowers and 64 white flowers. Assuming Hardy-Weinberg equilibrium, what is the value of q (the recessive allele) for this population?
- 36
- 60
- 64
- 75
- 80
0.80
Which of the following is not a requirement for maintenance of Hardy-Weinberg equilibrium?
an increasing mutation rate
random mating
large population size
no migration
no natural selection
an increasing mutation rate
In a large, sexually reproducing population, the frequency of an allele changes from 0.6 to 0.2. From this change, one can most logically assume that, in this environment,
the allele is neutral.
the allele mutates readily.
random processes have changed allelic frequencies.
there is no sexual selection.
the allele reduces fitness.
the allele reduces fitness.
Through time, the movement of people on Earth has steadily increased. This has altered the course of human evolution by increasing
nonrandom reproduction.
geographic isolation.
genetic drift.
mutations.
gene flow.
gene flow.
Gene flow is a concept best used to describe an exchange between
species.
males and females.
populations.
individuals.
chromosomes.
populations
The Darwinian fitness of an individual is measured by
the number of its offspring that survive to reproduce
the number of supergenes in the genotype
the number of mates it attracts.
its physical strength.
how long it lives.
the number of its offspring that survive to reproduce
If a phenotypic polymorphism lacks a genetic component, then
the environment cannot affect its abundance
natural selection cannot act upon it to make a population better adapted over the course of generations.
it cannot affect an individual’s ability to survive
it must exhibit quantitative variation.
all of the above
natural selection cannot act upon it to make a population better adapted over the course of generations.
on 39
When we say that an individual organism has a greater fitness than another individual, we specifically mean that the organism lives longer than others of its species. competes for resources more successfully than others of its species. mates more frequently than others of its species. utilizes resources more efficiently than other species occupying similar niches. leaves more viable offspring than others of its species.
When we say that an individual organism has a greater fitness than another individual, we specifically mean that the organism
Which of the following statements best summarizes evolution as it is viewed today?
It is goal-directed
It represents the result of selection for acquired characteristics.
It is synonymous with the process of gene flow.
It is the descent of humans from the present-day great apes.
It is the differential survival and reproduction of the most fit phenotypes.
It is the differential survival and reproduction of the most fit phenotypes.
An African butterfly species exists in two strikingly different color patterns.
directional selection
stabilizing selection
disruptive selection
disruptive selection
Most Swiss starlings produce four to five eggs in each clutch.
directional selection
stabilizing selection
disruptive selection
stabilizing selection
Fossil evidence indicates that horses have gradually increased in size over geologic time
directional selection
stabilizing selection
disruptive selection
directional selection
The average birth weight for human babies is about 3 kg.
directional selection
stabilizing selection
disruptive selection
stabilizing selection
A certain species of land snail exists as either a cream color or a solid brown color. Intermediate individuals are relatively rar
directional selection
stabilizing selection
disruptive selection
disruptive selection
Pathogenic bacteria found in many hospitals are antibiotic resistant.
directional selection
stabilizing selection
disruptive selection
directional selection
In many animal species, mature males are much larger than mature females. This size difference can be attributed to
male hormones having a more positive effect on body size than female hormones do.
the operation of intrasexual selection.
females preferentially selecting larger males as mates.
A and B only
A, B, and C
A, B, and C
What is the result of natural selection?
a chance change in the gene pool of a small population
the entry of alleles into a population due to immigration
a change in the gene pool of a population due to differential reproductive success
a change in allelic frequencies due to mutation
the loss of alleles from a population due to emigration
a change in the gene pool of a population due to differential reproductive success
All the genes in a population are the population’s
gene pool.
fitness.
genotype.
gene flow.
phenotype.
gene pool.
No two human individuals are alike, except for identical twins. The chief cause of the variation among individuals is
new mutations that occurred in the preceding generation.
sexual recombination.
genetic drift due to the small size of the population.
geographic variation within the population.
environmental effects.
sexual recombination.
Road construction has isolated a small portion of a beetle population from the main population. After a few generations, this new population exhibits dramatic genetic differences from the old one, most likely because
mutations are more common in the new environment.
allele frequencies among the stranded beetles differed by chance from those in the parent population’s gene pool and subsequent genetic drift caused even more divergence from the original gene pool.
the new environment is different from the old, favoring directional selection.
gene flow increases in a new environment.
members of a small population tend to migrate, removing alleles from the gene pool
allele frequencies among the stranded beetles differed by chance from those in the parent population’s gene pool and subsequent genetic drift caused even more divergence from the original gene pool.
Which of the following applies to both anagenesis and cladogenesis?
branching
increased diversity
speciation
more species
adaptive radiation
speciation
Which of the various species concepts identifies species based on the degree of genetic exchange between their gene pools?
phylogenetic
ecological
biological
morphological
paleontological
biological
There is still some controversy among biologists about whether Neanderthals should be placed within the same species as modern humans, or into a separate species of their own. Most DNA sequence data analyzed so far indicate that there was probably little or no gene flow between Neanderthals and Homo sapiens. Which species concept is most applicable in this example?
paleontological
phylogenetic
ecological
morphological
biological
biological
You are confronted with a box of preserved grasshoppers of various species that are new to science and have not been describe Your assignment is to separate them into species. There is no accompanying information as to where or when they were collecte Which species concept will you have to use?
biological
phylogenetic
ecological
paleontological
morphological
morphological
Some species of Anopheles mosquito live in brackish water, some in running fresh water, and others in stagnant water. What type of reproductive barrier is most obviously separating these different species?
habitat isolation
temporal isolation
behavioral isolation
gametic isolation
postzygotic isolation
habitat isolation
Which of the following must occur during a period of geographic isolation in order for two sibling species to remain genetically distinct following their geographic reunion in the same home range?
prezygotic barriers
postzygotic barriers
ecological isolation
reproductive isolation
temporal isolation
reproductive isolation
For each description of reproductive isolation, select the option that best describes it. two species of orchids with different floral anatomy
gametic
temporal
behavioral
habitat
mechanical
mechanical
For each description of reproductive isolation, select the option that best describes it. two species of trout that breed in different seasons
gametic
temporal
behavioral
habitat
mechanical
temporal
For each description of reproductive isolation, select the option that best describes it. two species of meadowlarks with different mating songs
gametic
temporal
behavioral
habitat
mechanical
behavioral
Two species of frogs belonging to the same genus occasionally mate, but the offspring do not complete development. What is the mechanism for keeping the two frog species separate?
the postzygotic barrier called hybrid inviability
the postzygotic barrier called hybrid breakdown
the prezygotic barrier called hybrid sterility
gametic isolation
adaptation
the postzygotic barrier called hybrid inviability
A defining characteristic of allopatric speciation is
the appearance of new species in the midst of old ones.
asexually reproducing populations.
geographic isolation.
artificial selection.
large populations.
geographic isolation
The Hawaiian islands are a great showcase of evolution because of intense
ecological isolation and sympatric speciation.
adaptive radiation and allopatric speciation.
allopolyploidy and sympatric speciation.
cross-specific mating and reinforcement.
hybrid vigor and allopatric speciation.
adaptive radiation and allopatric speciation.
A rapid method of speciation that has been important in the history of flowering plants is
genetic drift.
paedomorphosis.
a mutation in the gene controlling the timing of flowering.
behavioral isolation.
polyploidy.
polyploidy.
Plant species A has a diploid number of 8. A new species, B, arises as an autopolyploid from The diploid number of B would probably be
4.
8.
16.
32.
64.
16.
According to the concept of punctuated equilibrium, the “sudden” appearance of a new species in the fossil record means that
the species is now extinct.
speciation occurred instantaneously.
speciation occurred in one generation.
speciation occurred rapidly in geologic time
the species will consequently have a relatively short existence, compared with other species
speciation occurred rapidly in geologic time
According to the concept of punctuated equilibrium,
natural selection is unimportant as a mechanism of evolution.
given enough time, most existing species will branch gradually into new species.
a new species accumulates most of its unique features as it comes into existence.
evolution of new species features long periods during which changes are occurring, interspersed with short periods of equilibrium or stasis.
transitional fossils, intermediate between newer species and their parent species, should be abundant.
a new species accumulates most of its unique features as it comes into existence.
Speciation
occurs at such a slow pace that no one has ever observed the emergence of new species.
occurs only by the accumulation of genetic change over vast expanses of tim
must begin with the geographic isolation of a small, frontier population.
proceeds at a uniform tempo across all tax
occurs via anagenesis and cladogenesis, but only the latter increases biodiversity.
occurs via anagenesis and cladogenesis, but only the latter increases biodiversity.
The biological species concept is not useful for organisms known only from fossils because
fossils are rarely preserved well enough to distinguish species based on morphology.
it is not possible to test reproductive isolation in fossil forms.
it is not possible to infer the types of habitats occupied by fossil forms before their extinction.
in examining fossil organisms, it is not possible to distinguish males from females.
the fossil record can only be used for studying anagenesis, but not cladogenesis
it is not possible to test reproductive isolation in fossil forms.
Which of the following factors would not contribute to allopatric speciation?
A population becomes geographically isolated from the parent population.
The separated population is small, and genetic drift occurs.
The isolated population is exposed to different selection pressures than the ancestral population.
Different mutations begin to distinguish the gene pools of the separated populations.
Gene flow between the two populations is extensiv
Gene flow between the two populations is extensivly
1) Which of the following factors weaken(s) the hypothesis of abiotic synthesis of organic monomers in early Earth’s atmosphere?
1. the relatively short time between intense meteor bombardment and the appearance of the first life-forms
2. the lack of experimental evidence that organic monomers can form by abiotic synthesis
3. uncertainty about which gases comprised early Earth’s atmosphere
A) 1 only
B) 2 only
C) 1 and 2
D) 1 and 3
E) 2 and 3
D
2) How were conditions on the early Earth of more than 3 billion years ago different from those on today’s Earth?
A) Only early Earth was intensely bombarded by large space debris.
B) Only early Earth had an oxidizing atmosphere.
C) Less ultraviolet radiation penetrated early Earth’s atmosphere.
D) Early Earth’s atmosphere had significant quantities of ozone.
A
4) Which of the following is the correct sequence of events in the origin of life? I. formation of protobionts II. synthesis of organic monomers III. synthesis of organic polymers IV. formation of DNA-based genetic systems A) I, II, III, IV B) I, III, II, IV C) II, III, I, IV D) II, III, IV, I
C
5) Which of the following is a defining characteristic that all protobionts had in common?
A) the ability to synthesize enzymes
B) a surrounding membrane or membrane-like structure
C) RNA genes
D) the ability to replicate RNA
B
12) Approximately how far back in time does the fossil record extend? A) 3.5 million years B) 5.0 million years C) 3.5 billion years D) 5.0 billion years
C
15) An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to
A) generate intense lightning storms.
B) change the atmosphere from oxidizing to reducing.
C) make it easier to maintain reduced molecules.
D) cause iron in ocean water and terrestrial rocks to rust (oxidize).
E) prevent the formation of an ozone layer.
D
16) Which of the following statements provides the strongest evidence that prokaryotes evolved before eukaryotes?
A) Prokaryotic cells lack nuclei.
B) The meteorites that have struck Earth contain fossils only of prokaryotes.
C) Laboratory experiments have produced liposomes abiotically.
D) Liposomes closely resemble prokaryotic cells.
E) The oldest fossilized cells resemble prokaryotes.
E
17) What is true of the Cambrian explosion?
A) There are no fossils in geological strata that are older than the Cambrian explosion.
B) Only the fossils of microorganisms are found in geological strata older than the Cambrian explosion.
C) The Cambrian explosion is evidence for the instantaneous creation of life on Earth.
D) The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record.
E) Recent evidence supports the contention that the Cambrian explosion may not have been as “explosive” as was once thought.
E
18) What is thought to be the correct sequence of these events, from earliest to most recent, in the evolution of life on Earth?
1. origin of mitochondria
2. origin of multicellular eukaryotes
3. origin of chloroplasts
4. origin of cyanobacteria
5. origin of fungal-plant symbioses
A) 4, 3, 2, 1, 5
B) 4, 1, 2, 3, 5
C) 4, 1, 3, 2, 5
D) 4, 3, 1, 5, 2
E) 4, 3, 1, 2, 5
C
21) Which of these observations gives the most support to the endosymbiotic theory for the origin of eukaryotic cells?
A) the existence of structural and molecular differences between the plasma membranes of prokaryotes and the internal membranes of mitochondria and chloroplasts
B) the similarity in size between the cytosolic ribosomes of prokaryotes and the ribosomes within mitochondria and chloroplasts
C) the size disparity between most prokaryotic cells and most eukaryotic cells
D) the observation that some eukaryotic cells lack mitochondria
B
27) The major evolutionary episode corresponding most closely in time with the formation of Pangaea was the A) Cambrian explosion. B) Permian extinctions. C) Pleistocene ice ages. D) Cretaceous extinctions.
B
54) Soon after the island of Hawaii rose above the sea surface (somewhat less than 1 million years ago), the evolution of life on this new island should have been most strongly influenced by A) genetic bottleneck. B) sexual selection. C) habitat differentiation. D) founder effect.
D
55) Upon being formed, oceanic islands, such as the Hawaiian Islands, should feature what characteristic, leading to which phenomenon?
A) mass extinctions, leading to bottleneck effect
B) major evolutionary innovations, leading to rafting to nearby continents
C) a variety of empty ecological niches, leading to adaptive radiation
D) adaptive radiation, leading to founder effect
E) overcrowding, leading to rafting to nearby lands
C
60) If the complex protein assemblage of the prokaryotic flagellum arose by the same general processes as those of the complex eyes of molluscs (such as squids and octopi), then
A) natural selection cannot account for the rise of the prokaryotic flagellum.
B) ancestral versions of this protein assemblage were either less functional or had different functions than modern prokaryotic flagella.
C) scientists should accept the conclusion that neither eyes nor flagella could have arisen by evolution.
D) we can conclude that both of these structures must have arisen through the direct action of an “intelligent designer.”
B
69) Fossilized stromatolites
A) all date from 2.7 billion years ago.
B) formed around deep-sea vents.
C) resemble structures formed by bacterial communities that are found today in some warm, shallow, salty bays.
D) provide evidence that plants moved onto land in the company of fungi around 500 million years ago.
E) contain the first undisputed fossils of eukaryotes and date from 2.1 billion years ago.
C
70) The oxygen revolution changed Earth’s environment dramatically. Which of the following took advantage of the presence of free oxygen in the oceans and atmosphere?
A) the evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules
B) the persistence of some animal groups in anaerobic habitats
C) the evolution of photosynthetic pigments that protected early algae from the corrosive effects of oxygen
D) the evolution of chloroplasts after early protists incorporated photosynthetic cyanobacteria
E) the evolution of multicellular eukaryotic colonies from communities of prokaryotes
A
71) Which factor most likely caused animals and plants in India to differ greatly from species in nearby southeast Asia?
A) The species have become separated by convergent evolution.
B) The climates of the two regions are similar.
C) India is in the process of separating from the rest of Asia.
D) Life in India was wiped out by ancient volcanic eruptions.
E) India was a separate continent until 45 million years ago.
E
72) Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception.
A) vacant ecological niches
B) genetic drift
C) colonization of an isolated region that contains suitable habitat and few competitor species
D) evolutionary innovation
E) an adaptive radiation in a group of organisms (such as plants) that another group uses as food
B
73) Which of the following steps has not yet been accomplished by scientists studying the origin of life?
A) synthesis of small RNA polymers by ribozymes
B) abiotic synthesis of polypeptides
C) formation of molecular aggregates with selectively permeable membranes
D) formation of protocells that use DNA to direct the polymerization of amino acids
E) abiotic synthesis of organic molecules
D
Similarity resulting from common ancestry is called
homology
remnants of of features that served a function in the organism’s ancestors is called
vestigial structures
the independent evolution of similar features in different lineages is called
convergent evolution
when species share features because of convergent evolution it is called
analogous
when something is found no where else in the world it is called
endemic
when conditions favor individuals ehibiting one extreme of a phenotypic range
directional selection
when conditions favor individuals at both extremes of a phenotypic range
disruptive selection
