ANTH Ch. 3

true

A goal of evolutionary theory is to determine how genotype frequencies change over time.

random mating

A state of genetic equilibrium requires ________________.

true

Even though phenotypes may differ in their ability to reproduce, this does not imply that there is any effect on the frequency of associated genotypes.

false (When phenotypes differ in their ability to reproduce, the genotypes that are associated with them are also affected.)

Even though phenotypes may differ in their ability to reproduce, this does not imply that there is any effect on the frequency of associated genotypes. true or false?

0.40 (freq of aa + 1/2 x freq of heterozygote)

For a given gene in a population, there are two alleles, A and a. The frequency of the dominant homozygote, AA, is 0.50; the frequency of the heterozygote, Aa, is 0.20; and the frequency of the recessive homozygote, aa, is 0.30. What is the frequency of the recessive a allele? (Note: Give your answer with two decimal places.)

0.25

For a given gene with two alleles and three genotypes, the genotypic frequency of the heterozygote is 0.50 and the genotypic frequencies of the two homozygotes are equal to one another. What is the frequency of each homozygote? (Note: Use two decimal places in your response.)

natural selection works on different traits at the same time; natural selection is constrained by the laws of physics

Identify the reasons why natural selection does not always lead to the best possible phenotype being the most common phenotype. -Natural selection works on different traits at the same time. -Natural selection is constrained by the laws of physics. -Natural selection operates directly on genes. -Natural selection does not continue when a population is in a state of disequilibrium.

the populations of toads on each island will become more genetically distant from each other because the toad populations will be more isolated

Imagine that the islands of the Lesser Antilles in the Caribbean Sea are getting progressively smaller and further apart as water engulfs more of the islands each year. What is most likely to happen to the toad population there, knowing that toads are land animals and cannot survive in sea water? -The populations of toads on each island will become more genetically distinct from each other because the toad populations will be more isolated. -The populations of toads will become genetically stable, since toads cannot swim. -The toads will all migrate to the largest island and become one large population. -Each toad population will come to Hardy-Weinberg equilibrium.

it remains constant

In a population in Hardy-Weinberg equilibrium, what happens to the allele frequency? -It changes slowly. -It changes toward homozygosity. -It remains constant. -It changes at a constant rate.

0.48 (0.6x0.4x2)

In a stable population, the A allele has a frequency of 0.60, and the frequency of the a allele is 0.40. What is the frequency of the heterozygote? (Note: If the value is less than 1.0, give the answer with two decimal places.)

phenotypic expression depends on the environment in which the organism develops; complex phenotypic characters are affected by many genes

In the early 1930s, biologists Sewall Wright, Ronald A. Fisher, and J. B. S. Haldane demonstrated how Mendelian genetics could explain continuous variation. Identify the reasons for continuous variation of phenotypes. -Phenotypic expression depends on the environment in which the organism develops. -Complex phenotypic characters are affected by many genes. -Most populations do not practice random mating. -Genes blend during sexual reproduction.

true

Mutation can add new variation slowly to a population, even if much of the variation is protected from selection because intermediate phenotypes are produced that are favored by stabilizing selection. true or false?

false

Natural selection can affect gene frequencies by introducing new alleles to a population. true or false?

correlated response to selection

Natural selection does not affect only one character at a time, as demonstrated in the graphs. Identify the phenomenon illustrated by the two graphs below. -correlated response to selection -mutation -monotropic effect -mate guarding

there is hidden variation in every species, which means that the vast majority of the alleles in modern dogs were already present in wolves

On a visit to the zoo, you see a sign that says, "All modern breeds of dogs originally come from the wild wolf." How is it possible for animals that look so different to have come from the same original source? -Wolves migrated around the world and adapted to diverse environments; the different breeds of dogs arose at that time. -Since dogs are associated with humans, they are exposed to far more chemicals and forms of radiation, resulting in a higher mutation rate. -Dogs are entirely the result of a founder effect. -There is hidden variation in every species, which means that the vast majority of the alleles in modern dogs were already present in wolves.

male soapberry bugs guard female bugs more when there are more males than females

The graph below depicts the probability of mate guarding in soapberry bugs as a function of sex ratio. What can be concluded from this graph? -There are very few male soapberry bugs. -There is no relationship between mate guarding and the sex ratio of soapberry bugs. -Male soapberry bugs guard female bugs more when there are more males than females. -Male soapberry bugs guard female bugs more when there are more females than males.

true

The laws of physics and chemistry constrain evolutionary processes. true or false?

mutation

The ultimate source of all new genetic variation is ____________________.

true

The work of Wright, Fisher, and Haldane demonstrated how Mendelian genetics explained continuous variation, which became part of the modern synthesis. true or false?

when environments are stable

Under what conditions is behavioral plasticity most likely to evolve? -when environments are very stable -when behavior has recently changed -when environments are variable -when behavior is learned

behavioral plasticity

Variation in behavior that is responsive to variation in the environment is called ______________.

it is a male strategy to prevent other males from mating with an individual female

What is the function of mate guarding in soapberry bugs? -It protects the female from predation. -It is a male strategy to prevent other males from mating with an individual female. -It stops the female from moving. -It ensures sperm transfer, which takes several hours.

correlated traits

When two or more traits or characters are nonrandomly associated, scientists call them _________________.

mistakes in the replication of DNA; exposure to various chemicals; exposure to certain types of radiation

Which of the following circumstances can result in mutations? -amputation of a limb -mistakes in the replication of DNA -exposure to various chemicals -exposure to certain types of radiation

the integration of Darwinism and genetics

Which of the following is a correct assessment of the modern synthesis? -the integration of Mendelian genetics and anthropology -the integration of anthropology with Darwinism -the integration of Darwinism and genetics -the integration of genetics and field observations

it is the change in gene frequencies from one generation to the next

Which of the following is the best definition of evolution? -The purpose of evolution is to create bigger, stronger, and smarter organisms. -It is a change in gene frequencies due to mutation. -It is the change in gene frequencies due to genetic drift. -It is the change in gene frequencies from one generation to the next.

evolutionary change can occur through random genetic drift

Which of the following is true of evolutionary change? -Evolutionary change can only occur through mutation. -Selection produces optimal adaptations only at disequilibrium. -Evolutionary change can occur through random genetic drift. -Evolutionary change can occur if a population is completely wiped out.

all of the above

Which of the following statements are true regarding constraints by the laws of physics? -If an animal's linear dimensions of bone doubles, the cross-sectional areas will increase by a factor of 4. -If an animal's body size doubles due to natural selection, its weight or volume will increase by a factor of 8. -If an animal's linear dimensions are doubled, the ratio of surface area to volume is halved. -If thicker bones are heavier, it may impact other features, such as the animal's speed and quickness. -all of the above

a correlated response to selection can cause characters to change in maladaptive directions; correlated characters can occur because of pleiotropy

Which of the following statements regarding correlated characters are accurate? -A correlated response to selection can cause characters to change in maladaptive directions. -For correlated characters, selection that changes the mean value of one character is not necessarily associated with a change in the mean value of the other character. -Correlated characters can occur because of pleiotropy. -Correlated characters are nearly always positively correlated.

the rate of genetic drift depends on population size; in smaller populations, larger changes in gene frequencies can occur

Which of the following statements regarding genetic drift are accurate? -The rate of genetic drift depends on population size. -In smaller populations, larger changes in gene frequencies can occur. -Genetic drift causes isolated populations to become genetically similar to other isolated populations. -The most drastic impact of genetic drift occurs in large populations.

All genotypic frequencies must add up to 1.0 for a particular gene, since every individual has a genotype, they can be used to determine how evolutionary process control the distribution of certain alleles, a genotypic frequency is the fraction of the population that carries a particular genotype

Which of the following statements regarding genotypic frequencies are accurate? -All genotypic frequencies must add up to 1.0 for a particular gene, since every individual has a genotype. -There are usually only three genotypes for any given gene. -They can be used to determine how evolutionary process control the distribution of certain alleles. -A genotypic frequency is the fraction of the population that carries a particular genotype.

there is no blending of genes during sexual reproduction

Which of the following statements regarding how variation is maintained in a population is true? -There is no blending of genes during sexual reproduction. -Mutations add new variation very quickly. -Hidden variation has very minimal impact on the overall variation in a population. -Low mutation rates maintain variation because most of the variation is subject to natural selection.

selection does not operate directly on genes; selection cannot produce change unless there is variation in the population

Which of the following statements regarding the impact of natural selection on gene frequencies are accurate? -Selection does not operate directly on genes. -Selection cannot produce change unless there is variation in the population. -The strength and direction of selection depend on the genetics. -Selection does not operate directly on the phenotype; instead, it works on the genotypes.

all the genotypes have an equal ability to survive and reproduce

Why will genotype frequencies remain at Hardy-Weinberg proportions in a population? -All the genotypes have an equal ability to survive and reproduce. -The recessive allele is never more frequent than the dominant allele. -The heterozygote has the highest likelihood of surviving and reproducing. -The dominant homozygote is more likely to survive and reproduce than the recessive homozygote.