CWI BIOL 112 EXAM 1- CHAPTER 22 - 23 Mastering Biology
A hypothetical population of 500 cats has two alleles, T and t, for a gene that codes for tail length. (T is completely dominant to t.) The table below presents the phenotype of cats with each possible genotype, as well as the number of individuals in the population with each genotype. Assume that this population is in Hardy-Weinberg equilibrium. Recall that the Hardy-Weinberg equation is p 2 + 2pq +q 2 = 1. What is the frequency of cats with long tails in the population?
0.84
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
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?
1920
frequency of the heterozygous genotype
2pq
Suppose 64% of a remote mountain village can taste phenylthiocarbamide (PTC) and must, therefore, have at least one copy of the dominant PTC taster allele. If this population conforms to Hardy-Weinberg expectations for this gene, what percentage of the population must be heterozygous for this trait?
48%
A farmer wishes to develop a strain of high-yield corn that is also resistant to drought. He has the following individuals from the current year's crop: Individual A—Yield: 179 bushels/acre; drought resistance: high Individual B—Yield: 220 bushels/acre; drought resistance: low Individual C—Yield: 185 bushels/acre; drought resistance: medium Individual D—Yield: 140 bushels/acre; drought resistance: high Individual E—Yield: 200 bushels/acre; drought resistance: medium Which of the following crosses would produce the highest corn yield with the highest resistance to drought?
A and E
Which of the following organisms could be produced by artificial selection?
A cow that produces a large quantity of milk.
In the projected video showing the growth of bacteria, why did the bacteria grow up to the edge of the area with antibiotics, pause, then continue to grow across the area with antibiotics?
A few bacteria experienced random mutations in their DNA, which allowed some of them to grow even though antibiotics were present.
Which of the following correctly describes what the video referred to as a "microbial cure"?
Antibiotics are used to kill all of the infectious bacteria in a person.
Recall that the Hardy-Weinberg equation is p 2 + 2pq +q 2 = 1. what is the frequency of cats with short tails in the population? (q=0.40)
0.16
use the Hardy-Weinberg equation to predict the frequency of homozygous recessive cats in the next generation. p=0.60
0.16
Consider a population of wildflowers in which the frequency of the red allele CR is p = 0.7. What is the frequency of the white allele (CW ) in this population?
0.3
what is the frequency of cats that re homozygous dominant in the population? (p=0.60)
0.36
Use the Hardy-Weinberg equation and the frequency of the homozygous recessive generation (0.16) to estimate the frequency of the recessive allele t in the next genteration
0.40
what is the frequency of the t allele in the gene pool of this population? q^2= 0.16
0.40
use the Hardy-Weinberg equation to predict the frequency of heterozygous cats in the next generation. p=0.60
0.48
This Punnett square shows allele combinations for all possible genetic crosses in the wildflower population described in Part A. What are the expected genotype frequencies in the offspring generation?
0.49 CRCR (red flowers), 0.42 CRCW (pink flowers), 0.09 CWCW (white flowers)
A gene "L" is known to have two alleles, a dominant one (L) and a recessive (l) one. If the frequency of the dominant "L" allele in a population is 0.43, what is the frequency of the recessive "l" allele?
0.57
what is the frequency of the T allele in the gene pool of this population? p^2= 0.36
0.60
In Biston betularia, the peppered moth, M, the dark carbonaria allele, is dominant to m, the speckled allele. Prior to the industrial revolution (which covered the habitat of the moth with soot), the M allele accounted for only 10% of the population. After calculating the frequency of the m allele, determine what proportion of individuals in the population were mm, homozygous recessive
0.81
Which of the following is not an observation or inference on which natural selection is based?
Poorly adapted individuals never produce offspring.
Which of the following represents an idea that Darwin and Wallace learned from the writings of Thomas Malthus?
Populations tend to increase at a faster rate than their food supply normally allows.
Shorter wings allow cliff swallows to take off from the ground more vertically, enabling them to better avoid oncoming cars. As a result, cliff swallows in populations near highways with ___ wings have a survival advantage.
Shorter
The Grants witnessed strong selection during droughts in 1977 and 1985. Compare the two droughts.
Both droughts events provided strong natural selection on medium ground finch populations. Both droughts resulted in changes to food sources that favored the survival of some medium ground finches over others.
Darwin and Wallace made independent observations in different parts of the world. Which statements are true?
Both witnessed nature up close and realized it was a battlefield with massive casualties. Both collected huge numbers of specimens and realized that individuals vary within species. Both observed slightly different species on nearby islands and concluded that species could change over time.
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.
Began the convention of naming species with two names (a binomial): a genus and a species epithet.
Carolus Linneaus
Proposed a nested hierarchical scheme for classifying organisms that is still used today.
Carolus Linneaus
Which of the following statements best explains why modification or change in an organ or tissue during the lifetime of an individual is not inherited?
Characteristics acquired during an organism's life are generally not passed on through genes.
Proposed that new species arise very slowly over time when individuals that are born with favorable traits leave more offspring, resulting in an increase in the favorable traits in the population.
Charles Darwin
Proposed that the same geologic processes are operating today as in the past, and at the same slow, steady rate
Charles Lyell
Which of the following observations led to Darwin's major inferences?
Members of a population vary in their heritable traits Although organisms can produce huge numbers of offspring, many of these offspring do not survive.
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 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.
Which of the following statements describes the evolution by natural selection of Mycobacterium tuberculosis bacteria in their new environment?
The drug-resistance trait is an adaptation to the environment in which human hosts are medicated with the antibiotic rifampin.
Which observations led Darwin to establish a relationship between extinct and living animals?
The fossilized remains of giant sloths were found in places where smaller sloths now live. The bony shells of armadillos resembled the shells of ancient Glyptodon fossils.
What is the concern about using antibacterial and antimicrobial soaps?
The use of any chemical that kills bacteria can eventually lead to resistance to that chemical in the population of bacteria.
When Charles Darwin set sail on the HMS Beagle, what did he and most of his contemporary scientists think about the origin of species?
Most scientists, including Darwin, thought each species was specially created by God in its present form and did not change over time
What does Dr. Carroll mean when he says, "while mutation is random, natural selection is not"?
Mutations for advantageous traits are more likely to be passed on to the next generation. Natural selection favors some mutations. Natural selection acts on traits.
Which of the following statements about natural selection is true?
Natural selection favors individuals that reproduce more than others.
Does the ability of a Mycobacterium tuberculosis cell to infect a new host depend on its drug-resistant phenotype?
No, drug-susceptible cells and drug-resistant cells are equally likely to infect a new host.
Consider a wildflower population with the following allele and genotype frequencies. Frequency of the CR allele: p = 0.6 Frequency of the CW allele: q = 0.4 Frequency of CRCR : 50% Frequency of CRCW : 20% Frequency of CWCW : 30% Is this population in Hardy-Weinberg equilibrium?
No, the frequency of genotype CRCW is too low.
A particular antibiotic kills 99% of a bacterial population. What will be the result of the continued application of this antibiotic?
Over time, the antibiotic will become less effective at killing the bacteria.
In the lab, Nachman examined dark mice from two different populations living hundreds of miles apart. The mice looked nearly identical. Their dark color was caused by two different genes. What does this tell you?
Under very similar conditions, natural selection can favor very similar adaptations. There are at least two genes involved in creating dark mouse fur. Two completely different mutations in two separate genes can generate the same phenotype. Dark fur color evolved independently on each lava flow.
Which of these lists contains the four postulates of natural selection?
Variation in population, heritable variation, selection, differential survival or reproduction
Which one of the following researchers developed a theory of evolution that was very similar to Charles Darwin's?
Wallace
Scientific theories _____
are supported by, and make sense of, many observations
Based on the risk factors discussed in the video, which of the following groups would be most likely to develop the bone disease rickets?
children born to parents with dark skin living far from the equator
The role that humans play in artificial selection is to _____
choose which organisms reproduce
In evolutionary terms, an organism's fitness is measured by its _____
contribution to the gene pool of the next generation
Dolphins, sharks and extinct icthyosaurs (fossils of an aquatic dinosaur) all exhibit streamlined, torpedo-like shapes that help them move smoothly through the water. Such similar forms in distantly related organisms that live in similar environments are examples of _________ .
convergent evolution
Black-bellied seedcrackers have either small beaks (better for eating soft seeds) or large beaks (better for hard seeds). There are no seeds of intermediate hardness; therefore, which kind of selection acts on beak size in seedcrackers?
disruptive selection
Which type of selection tends to increase genetic variation?
disruptive selection
A challenge to traditional (pre-1860) ideas about species came from embryology, when it was discovered that _____
embryos of dissimilar organisms, such as sharks and humans, resemble each other
In the formula for determining a population's genotype frequencies, the "2" in the term 2pq is necessary because _____.
heterozygotes can come about in two ways
In the formula for determining a populations genotype frequencies, the "pq" in the term 2pq is necessary because _____
heterozygotes have two alleles
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
During the same time period, the wing length of cliff swallows killed on the roads generally
increased
Homozygotes with two sickle-cell alleles are selected against because they have a high risk of early mortality. However, heterozygotes with one sickle-cell allele experience few of the effects of sickle allele disease and are more likely to survive malaria than homozygotes with normal hemoglobin. The net effect of the combination of sickle cell allele and malaria has resulted in evolutionary change in areas where malaria is endemic by ____
increasing sickle-cell allele frequency
Human populations in low-UV environments tend to have more lightly pigmented skin. One explanation is that the selective pressure for dark skin decreases as UV intensity decreases. At the same time there is selection for lighter skin to absorb more UV radiation, which is needed for vitamin D production. What evidence supports the vitamin D hypothesis for the evolution of lighter skin tones?
indigenous peoples living at high latitudes have darker skin, but they eat foods rich in vitamin D
A heritable trait is one that
is determined at least in part by genes passed from parents to offspring
The theory of evolution through natural selection is considered a scientific theory because _____.
it is broad enough in scope to explain many observations it is supported by a massive body of evidence from many disciplines it is general enough to provide many testable hypotheses
Darwin used artificial selection of organisms such as pigeons, dogs, cattle and cole crops (cabbage, etc.) in his argument about the origin of species because
it suggests that nature can select for diverse forms from an ancestor just as humans do in selective breeding.
In most years where data was collected, the wings of cliff swallows killed on the roads were ____ than the wings of swallows found in the population at large.
longer
Genetic variation _____
must be present in a population before natural selection can act upon the population
According to the Hardy-Weinberg theorem, the frequencies of alleles in a population will remain constant if _____ is the only process that affects the gene pool.
sexual reproduction
Small Aristelliger lizards have difficulty defending territories, but large lizards are more likely to be preyed upon by owls. Which kind of selection acts on the adult body size of these lizards?
stabilizing selection
Women often have complications during labor while giving birth to very large babies, whereas very small babies tend to be underdeveloped. Which kind of selection is most likely at work regarding the birth weight of babies?
stabilizing selection
Which of the following is LEAST likely to cause antibiotic resistance?
taking the entire course of antibiotics as prescribed by the doctor
Catastrophism, the regular occurrence of geological or meteorological disturbances (catastrophes) as a cause of geological change and extinction of species, was Cuvier's attempt to explain the existence of _____
the fossil record
Darker skin is more prevalent in high-UV areas. Dr. Nina Jablonski proposed a hypothesis to explain the selective pressure for darker skin in these environments. On what evidence did she base this hypothesis?
the melanin in darkly pigmented skin protects circulating folate from being destroyed by UV radiation, and folate is important in human reproduction
Genetic drift is a process based on _____
the role of chance
A researcher mixes M. tuberculosis with and without the rpoB mutation and adds the bacteria to cell cultures. Half the cell cultures contain only standard nutrients, while the other half of the cell cultures contain rifampin and the standard nutrients. After many cell generations, the researcher finds that _____.
very few M. tuberculosis in the standard nutrient cell cultures carry the rpoB gene mutation, but almost all of the M. tuberculosis in the cell cultures with rifampin carry the rpoB mutation
In what way does natural selection depend on the specific environment in which an organism lives?
when the environment changes, traits that were beneficial to an organism may become harmful and vice versa.
frequency of the recessive allele
q
frequency of the homozygous recessive genotype
q^2
frequency of the recessive phenotype
q^2
Genetic drift
responsible for the bottleneck effect responsible for the founder effect causes allele frequencies to fluctuate randomly
Which of these individuals is a homozygous genotype?
AA
Which term describes a trait that increases an individual's ability to survive in a particular environment?
Adaptation
Which statement about variation is true?
All new alleles are the result of nucleotide variability.
After his journey on the HMS Beagle, Darwin made this now-famous sketch in his notebook. Which ideas does it represent?
All species are linked to one another by common ancestry. Species descend from other species just as naturally as children come from parents. All species are connected to one another in a "family tree."
Which of these gametes contain one or more recombinant chromosomes?
B, C, F, and G
Over time, bacteria have become increasingly resistant to antibiotics. Which of the following best explains this in terms of natural selection?
Bacteria that happen to have natural resistance to antibiotics survived and reproduced.
Suppose that a gene for coat color in mice has two alleles, B and b, where B is completely dominant and encodes a black coat color, and b is recessive and encodes a brown coat color. A mouse that is heterozygous has genotype _____, and its phenotype is _____
Bb; black
What is the meaning of Darwin's expression "descent with modification"?
Descent with modification refers to evolutionary change over time.
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.
Which statement about the beak size of finches on the island of Daphne Major during the prolonged drought of 1977 is true?
Each bird's survival was strongly influenced by the depth and strength of its beak as the drought persisted.
Discovered that the deeper fossils were found in layers of rock, the more they differed from current species. To explain these differences he proposed that periodic sudden calamitous events must have destroyed the older versions of species.
Georges Cuvier
Which term describes the ability of a trait to be passed on to offspring?
Heritability
Which of the following statements is an accurate combination of postulates 1 and 2 of natural selection?
Heritable variation exists for traits among individuals in a population.
Which of the following statements apply to the variation in human skin color?
Human skin color variation is primarily determined by the type and amount of melanin pigment in the skin. Human skin color variation evolved recently in hominid evolution, once some populations of our human ancestors migrated out of Africa. Human skin color variation likely evolved in response to differences in the intensity of sunlight around the world.
When dark-colored fur gives mice a 1% competitive advantage and 1% of the population begins with dark fur, in about 1000 years, 95% of the population will have dark fur. Which of the following statements is true?
If dark-colored rock pocket mice had a competitive advantage of 0.1%, it would take longer for 95% of the population to have dark fur.
Which of the following statements is an accurate combination of postulates 3 and 4 of natural selection?
Individuals experience differential success in their ability to survive or reproduce.
The film defines species as populations whose members don't interbreed. What keeps different Galápagos finch species from mating?
Individuals recognize and only respond to songs of their own species. Geographic isolation and different environments led to changes in traits that affected mating. Males only court females that have a similar beak and similar size.
The art of Bonsai is mentioned in your textbook (Figure 22.4) because
It is a counter example to the hypothesis of inheritance of acquired characteristics.
What must be true of any organ described as vestigial?
It must be homologous to some feature in an ancestor.
Proposed that new species arise when individual organisms change during their life time to improve their traits, and these changes are inherited by their offspring.
Jean-Baptiste de Lamarck
Which of the following statements about Lamarck is accurate?
Lamarck thought evolution had occurred.
Which pair of chickens should a farmer breed to produce larger chickens?
Large hen, large rooster
Which of the following statements accurately describes melanin's function?
Lighter skin has less of the dark-brown eumelanin that protects cells from UV damage
What did Wallace conclude from observing that the bones in manatee flippers look similar to the bones in a human arm and hand?
Manatees' arm and finger bones are evidence that manatees share a common ancestor with land mammals.
Genetic evidence supports which of the following explanations for the presence of 13 different finch species on the Galápagos islands?
Many years ago, a small population of a single finch species migrated to the islands and evolved into the current 13 species.
Identify the pair of homologous structures.
Maple leaf and oak leaf
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.
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.
Darwin and Wallace independently arrived at the same conclusion that species change over time. Which observations supported their conclusions?
The bony shells of armadillos resembled fossilized shells from the extinct Glyptodon. Bird families clustered geographically: cockatoos in the Malay Archipelago and Australia, macaws and hummingbirds in the Americas. The fossilized remains of giant sloths were similar to the smaller, living sloths Darwin encountered. Tortoises from different Galapagos islands have distinct shells. Mockingbirds from different Galapagos islands had subtle, consistent differences. Birdwing butterflies were found throughout the Malay archipelago, but species differed slightly from island to island.
In 1977, medium ground finches on Daphne Major experienced a severe drought. The figure shows the beak depths of the initial population before the drought (red bars) and of the drought survivors (black bars). What do the data show?
The most common beak size of the initial population was 8.8 millimeters. A very small proportion (~5%) of the initial population with this beak size survived. Finches with larger beaks had a survival advantage in the 1977 drought. More than one-half of the initial population died during the drought.
The top figure shows beak sizes of the 1976 finch population before the drought of 1977 (red bars) and after the drought (black bars). The lower figure shows the beak sizes of the offspring of the drought survivors in 1978. What do these figures tell us?
The overall beak depths of the 1978 offspring population are larger the original 1976 population.
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.
In a bell-shaped curve, the x-axis (horizontal direction) of the graph represents which of the following?
The value of a particular characteristic; characteristics of an organism can include such traits as size and color.
As Wallace traveled the Malay Archipelago, he noticed that western islands had placental mammals, like monkeys. Eastern islands had marsupial mammals, like kangaroos. How did Wallace explain this distribution?
The western islands were once connected to Asia and the eastern islands had been connected to Australia. The islands had never been connected to each other
Why do dark-colored rock pocket mice on dark lava flows have white bellies?
There is no selection for dark bellies by visual predators.
Why did dark-colored rock pocket mice first appear in a population of light-colored rock pocket mice?
They have a genetic mutation that affects their fur color.
How did the Grants test their hypothesis that differences in birds' songs can keep different species of finches from breeding with one another?
They played the songs of medium ground finches and cactus finches through a loudspeaker to see which species responded to each song.
researchers gathered data on the number of cliff swallow road kills they observed while driving between nest sites in Nebraska. The data cover a period of about 30 years and date back to the time when cliff swallows first started to nest under highway overpasses. As the graph shows, the number of road kills observed declined sharply over time. The data led the researchers to ask themselves this question: What caused this decline? Which of the following are testable hypotheses that could explain the researchers' data? Select all that apply.
Traits that help individuals avoid being hit by cars have evolved through natural selection in the cliff swallow population. Scavenger population sizes have increased, and more road-killed swallows get eaten before they can be found. The population size of cliff swallows living near roads has decreased over time.
Mutations are always __________
a change in an individual's DNA
Prior to the work of Lyell and Darwin, the prevailing belief was that Earth is _____
a few thousand years old, and populations are unchanging
Many crustaceans (for example, lobsters, shrimp, and crayfish) use their tails to swim, but crabs have reduced tails that curl under their shells and are not used in swimming. This is an example of _____ (choose all that apply).
a homologous structure a vestigial trait
gene flow
a result of the movement of fertile individuals or their gametes can introduce new alleles into a population's gene pool
Consider the following mutations to the nucleotide sequence of a gene. Which of these mutations would not alter the reading frame (the triplet grouping of nucleotides that is read during translation) of the gene's genetic message?
a single nucleotide-pair substitution
An adaptation is _____.
a trait that gives an organism a reproductive advantage in the current environment
Given the frequency of the alleles in Part 1, out of 10,000 individuals, approximately how many are expected to be carriers of cystic fibrosis, that is heterozygotes who don't have the disease, but who can transmit it to their offspring because they have on copy of the recessive allele?
about 600
Shorter wings are a(n) ___in this population. Alleles for shorter wings were ___ in the general population.
adaptation; already present
To calculate the frequency of the brown allele, count the number of ___ and divide by the total number of ___ in this population.
allele; alleles
evolution
can happen whenever any of the conditions for Hardy-Weinberg equilibrium are not met
natural selection
cannot cause a harmful allele to become more common consistently causes a population to become better adapted to its environment a result of differential success in reproduction
hypothesis: scavenger population sizes have increased, and more road-killed swallows get eaten before they can be found
data collected: Avian scavengers did not increase during this time and terrestrial scavengers probably did not increase hypothesis supported: no
hypothesis: The population size of cliff swallows living near roads has decreased over time
data collected: The total number of cliff swallow nests near roads increased during this time hypothesis supported: no
Hypothesis: Traits that help individuals avoidbeing hit by cars have evolved through natural selection in the cliff swallow population
data collected: The wing shapes of swallows killed on roads differ from those of the general population hypothesis supported: yes
hypothesis: the number of cars driving on these roads has decreased over time
data collected: car traffic stayed the same or increased during this time hypothesis supported: no
From 1984 to 2012, the wing length of cliff swallows in the general population generally
decreased
Which of the following is the most predictable outcome of increased gene flow between two populations?
decreased genetic difference between the two populations
Long necks make it easier for giraffes to reach leaves high on trees, while also making them better fighters in "neck wrestling" contests. In both cases, which kind of selection appears to have made giraffes the long-necked creatures they are today?
directional selection
In those parts of equatorial Africa where the malaria parasite is most common, the sickle-cell allele constitutes 20% of the β hemoglobin alleles in the human gene pool. In the United States, the parasite that causes malaria is not present, but African-Americans whose ancestors were from equatorial Africa are present. What should be happening to the sickle-cell allele in the United States, and what should be happening to it in equatorial Africa?
directional selection; stabilizing selection
Darwin and Wallace's theory of evolution by natural selection was revolutionary because it _____.
dismissed the idea that species are constant and emphasized the importance of variation and change in populations
Anopheles mosquitoes, which carry the malaria parasite, cannot live above elevations of 5,900 feet. In addition, oxygen availability decreases as altitude increases. Low oxygen levels increase sickling in red blood cells in both homozygotes with sickle-cell disease and heterozygotes, causing symptoms that can be fatal. Consider a hypothetical human population that is adapted to life on the slopes of Mt. Kilimanjaro in Tanzania, a country in equatorial Africa. Mt. Kilimanjaro's base is about 2,600 feet above sea level and its peak is 19,341 feet above sea level. If the incidence of the sickle-cell allele in the population is plotted against altitude (feet above sea level), which of the following distributions is most likely, assuming little migration of people up or down the mountain?
downward slant
Cystic fibrosis is a genetic disorder in homozygous recessives that causes death during the teenage years. If 9 in 10,000 newborn babies have the disease, what are the expected frequencies of the dominant (A1) and recessive (A2) alleles according to the Hardy-Weinberg model?
f(A1) = 0.9700, f(A2) = 0.0300
True or false? Heterozygote advantage refers to the tendency for heterozygous individuals to have better fitness than homozygous individuals. This higher fitness results in less genetic variation in the population.
false
The wing of a bat is homologous to the _____ of a whale.
flipper
If the original finches that blew over to the Galápagos from South America already had different allele frequencies from the parental population of South American finches, even before adapting to the Galápagos, this would have been an example of
founder effect and genetic drift
The ease with which humans travel across the globe is likely to increase _____
gene flow
All the genes in a population are that population's _____.
gene pool
Allele frequencies in a gene pool may shift randomly and by chance. What is this random shift called?
genetic drift
The data suggest that, over time, ___ resulted in the evolution of shorter wings in the cliff swallow population.
natural selection
What is the only evolutionary mechanism that consistently leads to adaptive evolution?
natural selection
Crossing over, resulting in an increase in genetic variation, occurs between _____.
nonsister chromatids of homologous chromosomes
When Cuvier considered the fossils found in the vicinity of Paris, he concluded that the extinction of species ________.
occurs, but that there is no evolution
Fossils found in strata reveal that ________.
older strata carry fossils that differ greatly from living organisms
frequency of the dominant allele
p
frequency of the homozygous dominant genotype
p^2
frequency of the dominant phenotype
p^2 + 2pq
Charles Darwin _____.
proposed natural selection as the mechanism of evolution
