Allelic Frequency Changes Practice Problems

In a population that is in Hardy-Weinberg equilibrium, 20 individuals have the homozygous recessive genotype (aa), 120 individuals have the homozygous dominant genotype (AA), and 60 individuals have the heterozygous genotype (Aa). What is the population's entire gene pool?

In a population of 1000 individuals, 360 are homozygous dominant (AA), 480 are heterozygous (Aa), and 160 are homozygous recessive (aa) for a particular trait. What is the total number of "A" alleles in this population?

In a population of 100 individuals, 60 have the dominant phenotype and 40 have the recessive phenotype for a particular trait. If the recessive allele is designated as "a", what is the frequency of the "aa" genotype in this population?

Which of the following best describes the term ''F ''?

Which of the following statements about the common ancestor(s) of an inbred individual is true?

Can the inbreeding coefficient, or F, be calculated for any individuals who may have been the result of consanguinity, or mating between individuals who are closely related to each other? 

In which generation are the grandchildren of the common ancestors of the inbred individual present?

In a family with five generations, the parents in Generation III (III-2 and III-3) are first cousins. The daughter of III-2 marries the son of III-3 (second cousins). Which individual(s) in this family is/are inbred?

Who among the following individuals are the result of inbreeding in the partial pedigree of the British royal family?

Inbreeding is the mating of closely related individuals, such as siblings or cousins. Which of the following benefits of inbreeding leading to the evolution of assortative mating is incorrect?

A genetic bottleneck is an event in which a population is drastically reduced in size, often due to a catastrophic event such as a natural disaster, disease outbreak, or overhunting. Which of the following statements best describes how genetic bottlenecks affect the genetic diversity of a population?

In a small isolated island population of birds, only a few individuals were responsible for founding the entire population. This is an example of the founder effect. Which of the following is a likely consequence of the founder effect?

Which of the following is considered a genetic consequence of inbreeding?

Genetic drift in a small population over time can develop new characteristics that are different from the main population, which can then lead to:

The effect of which of the following evolutionary processes is more pronounced in small populations than in large populations?

Which of the following is the result of natural selection operating in favor of heterozygotes?

Gene flow, mutation, genetic drift, and natural selection are the significant forces that change the:

About 1 in 2500 infants suffer from cystic fibrosis (CF) in a small population that experienced a catastrophic event on a small island. Determine the frequency of the carriers.

About 1 in 625 infants suffer from cystic fibrosis (CF) in a small population that experienced a catastrophic event on a small island. Determine the frequency of the recessive allele that produces CF.

What effect does a genetic bottleneck have on population genetic diversity?

Which of the following alters the allele frequencies in a population that survives a catastrophic event?

In which of the following do you expect the genotype frequency to be reduced because of inbreeding? (Assume allele A to be dominant over allele a).

The mating of related individuals who share a greater proportion of alleles with one another than with random members of a population is called:

The two mechanisms of genetic drift are the founder effect and the bottleneck effect. Which of the following statements regarding these two mechanisms is incorrect?

Which of the following does not change allele frequencies?

In a population of 600 men, 150 suffer from hemophilia. Determine the frequency for the hemophilia allele carried on the X chromosome.

Which of the following populations experiences rapid changes in allele frequency?

A population has the following genotype frequencies: AA = 0.49, Aa= 0.42, and aa= 0.09. Determine the allele frequencies.

Natural selection and genetic drift are the mechanisms for evolution. Which of the following statements regarding these two mechanisms is incorrect?

What does an inbreeding coefficient of F = 1/2 represent?

What does the inbreeding coefficient measure in a population or pedigree?

In a small isolated population of endangered birds, a group of individuals started mating with close relatives due to limited mate availability. Over several generations, the inbreeding coefficient for a particular pair of birds, A and B, was calculated to be F = 0.125. What does this coefficient represent?

In a hypothetical pedigree, which of the following inbreeding coefficients corresponds to a situation where six generations of individuals are each inbred with a half-sibling, resulting in an inbreeding coefficient of F?

Offspring of biologically related persons are subject to the possible effects of inbreeding, such as congenital birth defects.   Inbreeding results in the phenotypic expression of deleterious recessive alleles within a population. As a result, first-generation inbred individuals show physical and health defects. Some of the defects include:

Which type of selection makes the beneficial mutations become more prevalent?

Adaptive evolution is the evolutionary changes in an organism that make it suitable for its habitat. The main two factors that influence adaptive mutations include the rate of mutation and the population size. Based on population size, rapid adaptive mutations will occur because:

Which of the following reproductive isolations is brought about by variations in mating habits?

Which of the following is a primary barrier to interbreeding between different species?

Which of the following types of genetic changes can cause polyploidization, leading to speciation?

What effect does inbreeding have on genetic diversity?

The probability that two alleles are identical by descent in an individual is termed:

Given that the initial frequency of the B resistance allele in the corn borer population is 0.3. What would be the frequency of the recessive genotype bb.

An individual has an inbreeding coefficient of 0.1. It means that:

All of the following are factors that contribute to maintaining high levels of genetic variation in natural populations, EXCEPT:

Which of the following is the first Mendelian trait identified in humans?

The primary way in which mutation contributes to speciation is by:

Which of the following is the probability that the offspring of two individuals who do not express a recessive trait will express it, given that 5% of the population in equilibrium expresses the trait?

What is the bottleneck effect in population genetics?

Which of the following best defines allelic frequency?

In a population of 1000 individuals, 160 are homozygous recessive for a particular trait. What is the frequency of the dominant allele in the population if the population is in Hardy-Weinberg equilibrium?

Which of the following is not an indication that two individuals are two different species?

A population can undergo a drastic but temporary reduction in size. Although the population can recover in terms of population size, genetic diversity has been significantly reduced. This process is called:

Next-generation sequencing (NGS) can determine the DNA or RNA sequence to study genetic variation. Since many organisms have extremely long genomes, what is the initial step of NGS that makes DNA sequence analysis possible?

In purifying selection, which of the following variation is removed from the population?