Biology Unit 4
A fruit fly population has a gene with two alleles, A1 and A2. Tests show that 70% of the gametes produced in the population contain the A1 allele. If the population is in Hardy-Weinberg equilibrium, what proportion of the flies carry both A1 and A2?
0.42
Plant species A has a diploid number of 12. Plant species B has a diploid number of 16. A new species, C, arises as an allopolyploid from A and B. The diploid number for species C would probably be
28.
Select the most accurate statement about the interaction between a tree and its physical environment.
A tree and its physical environment alter each other.
The universal genetic language of DNA is common to virtually all organisms on Earth, however diverse. What is the best explanation for this fact?
All living things share a common genetic language of DNA because they share a common ancestry
The original habitat of the North American maggot fly, Rhagoletis pomonella, was native hawthorn trees. About 200 years ago, some populations colonized newly introduced apple trees. The two populations are still classified as subspecies, but sympatric speciation is under way. What has contributed to incipient speciation in the maggot fly?
Because apples mature more quickly than hawthorn fruit, the apple-feeding flies have been selected for more rapid development.
What happened in the soapberry bug population in central Florida when the bugs began to feed on seeds from the goldenrain tree fruits which are much closer to the fruit surface?
Bugs with shorter beaks had more access to food, allowing them to produce more offspring
What is the meaning of Darwin's expression "descent with modification"?
Descent with modification refers to evolutionary change over time.
Which of the following factors would not contribute to allopatric speciation?
Gene flow between the two populations is extensive.
Which of the following statements best distinguishes hypotheses from theories in science?
Hypotheses usually are relatively narrow in scope; theories have broad explanatory power.
Which of the following best describes the logic of scientific inquiry?
If my hypothesis is correct, I can expect certain test results.
Which factor most likely caused animals and plants in India to differ greatly from species in nearby southeast Asia?
India was a separate continent until 45 million years ago.
Select the correct statement about the process of scientific inquiry.
It is possible to test hypotheses, such as those involving historical events, without conducting experiments.
Identify the pair of homologous structures.
Maple leaf and oak leaf
Which example illustrates a property that emerges at the community level?
Metabolic cooperation between prokaryotic cells forms a biofilm that allows bacterial colonies to transport nutrients and wastes. Biofilms may damage industrial equipment or cause tooth decay.
Which statement about natural selection on early Earth is correct?
Natural selection could act on a population of proto-cells on early Earth, selecting for those that were stable and had self-replicating, catalytic RNA that allowed them to grow and divide to produce similar daughter proto-cells.
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.
Which of the following is not an observation or inference on which natural selection is based?
Poorly adapted individuals never produce offspring.
Adaptive radiations on archipelagos (island chains) represent some of the best-understood speciation events. Why is an ancestral species more likely to give rise to multiple descendent species on an archipelago than on an equal-sized area of mainland?
Populations on nearby islands are more likely to be genetically isolated than populations that are equally close to one another on the mainland.
A paleontologist finds a new tyrannosaur in a site she is excavating, and wishes to date the fossil. What is the most likely method she will use
She will infer the age of the fossil by dating layers of volcanic rock above and below the stratum containing the fossil.
Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency.
Some RNA molecules are important catalysts in modern cells.
Within six months of effectively using methicillin to treat S. aureus infections in a community, all new infections were caused by MRSA. How can this result best be explained?
Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency.
Which of the following observations helped Darwin shape his concept of descent with modification?
South American temperate plants are more similar to the tropical plants of South America than to the temperate plants of Europe
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.
Select the correct statement describing sympatric speciation.
Sympatric speciation can occur in a single generation.
What was the "oxygen revolution," which took place 2.3 billion years ago?
The "oxygen revolution" was the rapid increase in atmospheric oxygen that took place 2.3 billion years ago, dooming many prokaryotic groups.
The fruit fly Drosophila melanogaster has an allele that confers resistance to DDT and similar insecticides. Laboratory strains of D. melanogaster have been established from flies collected in the wild in the 1930s (before the widespread use of insecticides) and the 1960s (after 20 years of DDT use). Lab strains established in the 1930s have no alleles for DDT resistance. In lab strains established in the 1960s, the frequency of the DDT-resistance allele is 37%. Which statement is correct?
The evolutionary fitness associated with the heritable trait of DDT resistance changed once DDT use became widespread.
Which of the following is an example of qualitative data?
The fish swam in a zigzag motion.
Two observations can be made regarding this study: The lap94 allele helps mussels maintain osmotic balance in water with a high salt concentration, but it is costly to use in less salty water. Mussels produce larvae that can disperse long distances before they settle on rocks and grow into adults.
The frequency of the lap94 allele at different sites results from an interaction between selection and gene flow.
How do the data from sites 9-11 compare with the data from the sites within the Sound?
The frequency of the lap94 allele is higher at sites 9-11 than it is within the Sound; however, the northeast edge of the Sound has nearly the same frequency of the lap94 allele as do sites 9-11.
How long does it take new species to form on Earth?
The time required varies considerably.
Bird guides once listed the myrtle warbler and Audubon's warbler as distinct species. Recently, these birds have been classified as eastern and western forms of a single species, the yellow-rumped warbler. Which of the following pieces of evidence, if true, would be cause for this reclassification?
The two forms interbreed often in nature, and their offspring have good survival and reproduction.
Which statement correctly describes the role of chance in evolution?
The ultimate source of new alleles is mutation, random changes in the nucleotide sequences of an organism's DNA.
Which of these examples illustrates deductive reasoning?
You learned in elementary school that as temperature drops, liquids change into solid form. You are given an unfamiliar liquid and hypothesize that it will become solid if you put it in the freezer.
A genetic change that caused a certain Hox gene to be expressed along the tip of a vertebrate limb bud instead of farther back helped make possible the evolution of the tetrapod limb. This type of change is illustrative of
a change in a developmental gene or in its regulation that altered the spatial organization of body parts.
All the organisms on your campus make up
a community.
Males of different species of the fruit fly Drosophila that live in the same parts of the Hawaiian Islands have different elaborate courtship rituals. These rituals involve fighting other males and making stylized movements that attract females. What type of reproductive isolation does this represent?
behavioral isolation
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 steps has not yet been accomplished by scientists studying the origin of life?
formation of protocells that use DNA to direct the polymerization of amino acids
If the nucleotide variability of a locus equals 0%, what is the gene variability and number of alleles at that locus?
gene variability = 0%; number of alleles = 1
Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception.
genetic drift
Allele frequencies in a gene pool may shift randomly and by chance. What is this random shift called?
genetic drift
There are 40 individuals in population 1, all with genotype A1A1, and there are 25 individuals in population 2, all with genotype A2A2. Assume that these populations are located far from each other and that their environmental conditions are very similar. Based on the information given here, the observed genetic variation is most likely an example of
genetic drift.
DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that
humans and chimpanzees share a relatively recent common ancestor.
Natural selection changes allele frequencies because some _______ survive and reproduce more successfully than others.
individuals
According to the punctuated equilibria model,
most new species accumulate their unique features relatively rapidly as they come into existence, then change little for the rest of their duration as a species.
Fossilized stromatolites
resemble structures formed by bacterial communities that are found today in some warm, shallow, salty bays.
The largest unit within which gene flow can readily occur is a
species.
A controlled experiment is one that
tests experimental and control groups in parallel
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?
the evolution of cellular respiration, which used oxygen to help harvest energy from organic molecules
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
Which of the following best demonstrates the unity among all organisms?
the structure and function of DNA
Systems biology is mainly an attempt to
understand the behavior of entire biological systems.