Question 1

In a small population of cockroaches living in your kitchen,only a few roaches mate in one year.This can lead to random changes in allele frequency in the population through ________

Accepted Answer

Genetic drift refers to changes in allele frequency due to random events such as chance mating, deaths, or births. In a small population of cockroaches with only a few individuals mating, genetic drift is likely to have a significant impact on allele frequencies over time.

Question 2

For a gene with two alternative alleles,B and b,the term q² in the Hardy-Weinberg equation represents

Accepted Answer

The term q² in the context of the Hardy-Weinberg equation does not directly correspond to any standard notation used in genetics. However, based on the options provided and understanding Hardy-Weinberg principles, the closest interpretation would be related to genotype frequencies. In Hardy-Weinberg equilibrium, the frequency of the homozygous recessive genotype (bb) is represented by q^2, where q is the frequency of the recessive allele (b). Since the provided term does not match standard notation, interpreting it to represent the frequency of the bb genotype is a logical deduction given the context of the question and the options available.

Question 3

For a gene with two alternative alleles,A (with a frequency of p)and B (with a frequency of q),the term in the algebraic form of the Hardy-Weinberg equilibrium for the heterozygote genotype frequency is

Accepted Answer

The Hardy-Weinberg equilibrium formula for the heterozygote genotype frequency is 2pq, where p and q are the frequencies of the two alleles. Therefore, option C, which gives the algebraic form of 2pq, is the correct choice. The other options do not provide the correct calculation for the heterozygote genotype frequency in the Hardy-Weinberg equilibrium.

Question 4

Female cardinals select male mates in part based on their bright red color.What effect would this have on a cardinal population that was in Hardy-Weinberg equilibrium?

Accepted Answer

The Hardy-Weinberg principle assumes that there is no selection for any particular genotype. However, if female cardinals prefer mates based on their bright red color, this introduces a form of sexual selection. Males with the alleles for brighter red coloration would have a reproductive advantage, leading to an increase in the frequency of these alleles in the population over time, deviating from the predictions of Hardy-Weinberg equilibrium.

Question 5

About 80% of the alleles present in thoroughbred horses can be dated back to 31 known ancestors from the late eighteenth century.As a result,one would expect ________

Accepted Answer

The fact that so much of the genetic variation in thoroughbred horses can be traced back to a relatively small number of ancestors suggests that there is little variation in physiology and behavior among these horses. This is because their genes have been relatively fixed for a long time, meaning that there hasn't been much opportunity for new mutations or alternative allele combinations to arise.

Question 6

Animals that select mates that are phenotypically similar will have ________ when compared with Hardy-Weinberg predictions.

Accepted Answer

When animals select phenotypically similar mates, it is known as positive assortative mating. This can result in an increased frequency of homozygotes in the population, which is not in accordance with Hardy-Weinberg predictions. Therefore, the correct answer is D) more homozygotes.

Question 7

Some flowering plants cannot self-pollinate which increases their tendency to mate with phenotypically different mates,a process called disassortative mating.What effect would this have on a population in Hardy-Weinberg equilibrium?

Accepted Answer

Disassortative mating would increase the frequency of heterozygotes in the population, as individuals with different phenotypes are more likely to breed and produce heterozygous offspring. This would result in a deviation from Hardy-Weinberg equilibrium, as the expected frequency of heterozygotes would be higher than predicted by the Hardy-Weinberg equation.

Question 8

Gene flow,defined as the movement of genes from one population to another,can take place by migration,as well as

Accepted Answer

Gene flow can occur through mating between individuals of adjacent populations, allowing for the exchange of genetic material.

Question 9

The observation that most pureblood Native Americans have type O blood is best explained by ________

Accepted Answer

The observation that most pureblood Native Americans have type O blood is best explained by a founder effect, which is the reduced genetic diversity that results when a population is descended from a small number of ancestors.

Question 10

Certain small towns in the western United States have remained isolated and inbred since their settlement many years ago.Some alleles are more common in these communities as compared to the rest of the population.This effect is known as

Accepted Answer

The effect of certain alleles being more common in isolated small towns due to their settlement history is known as the founder effect. This is because the town's population was founded by a small group of individuals who carried a subset of the overall gene pool, leading to a higher frequency of certain alleles in the community.

Question 11

Hardy-Weinberg pointed out that the original proportions of the genotypes in a population would remain constant from generation to generation if certain assumptions are met.Which one of the following is not a Hardy-Weinberg condition?

Accepted Answer

Hardy-Weinberg assumes that the population is in Hardy-Weinberg equilibrium, meaning there is no evolution occurring. One of the assumptions that facilitates this equilibrium is that the population is composed of a single gene pool with no polymorphic loci, as this means there is no variation in the gene frequency.

Question 12

In a forest,trees that get more sunlight grow taller than other nearby trees.This is a form of ________

Accepted Answer

This is an example of directional selection. The selective pressure in this case is the availability of sunlight, which favors the taller trees. The shorter trees that do not receive as much sunlight are at a disadvantage and have reduced fitness, leading to a decrease in their frequency over time.

Question 13

An island is on the migration route of sea birds.This island also has abundant tree nesting birds that live on the island permanently and are not found on any other island.The tree nesting birds are more likely than the sea birds to be in Hardy-Weinberg equilibrium because:

Accepted Answer

The sea birds experience high immigration, which introduces new alleles and disrupts Hardy-Weinberg equilibrium. The tree nesting birds, being isolated, have less gene flow and are more likely to meet the conditions for Hardy-Weinberg equilibrium.

Question 14

You spray your kitchen with an insecticide to kill the cockroaches.A few survive and reproduce,producing a large healthy population in a few generations that all have similar genetic backgrounds.This is an example of ________

Accepted Answer

This scenario is an example of the bottleneck effect, where a significant reduction in population size (due to the insecticide) leaves a small surviving group that reproduces. This small group's genetic makeup becomes the basis for the future population, leading to reduced genetic diversity and a population that may be very different from the original.

Question 15

________ would keep a population in Hardy-Weinberg equilibrium.

Accepted Answer

Random mating would keep a population in Hardy-Weinberg equilibrium as it ensures that all individuals have an equal chance of mating with any other individual in the population, removing any bias in mate choice that could cause changes in allele frequencies. The other options - mutation, gene flow, genetic drift, and selection - all introduce changes to allele frequencies that can disrupt Hardy-Weinberg equilibrium.

Question 16

Cheetahs have been through a genetic bottleneck; evidence for this is that

Accepted Answer

A genetic bottleneck occurs when a population is drastically reduced in size, leading to a loss of genetic diversity. Cheetahs have experienced this bottleneck and as a result, there is very little genetic variability in the species.

Question 17

Being born with extra fingers on a hand is called polydactyly.This is more common in some populations in North America than others due to ________.

Accepted Answer

The prevalence of polydactyly in certain populations in North America is likely due to a founder effect, where a small group of individuals carrying the allele for extra fingers migrated to and founded these populations. This resulted in a higher frequency of the allele in those populations.

Question 18

In order for natural selection to occur within a population,certain conditions must be met.One such condition is

Accepted Answer

For natural selection to occur within a population, there must be phenotypic variations that are genetic, meaning they are inherited. These variations allow some individuals to have higher fitness and survive better in their environment, passing on their advantageous traits to their offspring. This process leads to a change in the genetic makeup of the population over time. Phenotypic differences resulting from environmental conditions (A) can be important in shaping phenotypic variation but are not enough for natural selection to occur. While mutations (B) can provide new genetic variation, they do not necessarily occur frequently or always result in advantageous traits. Immigration rates (C) can affect the genetic makeup of a population, but they are not necessary for natural selection. Heterozygosity (E) refers to the presence of different alleles within an individual, but it is not a necessary condition for natural selection to occur.

Question 19

If a population was in Hardy-Weinberg equilibrium,then ________ would occur in that population.

Accepted Answer

Hardy-Weinberg equilibrium is a theoretical model in population genetics, in which the relative frequencies of alleles and genotypes in a population remain constant from generation to generation, if certain conditions are met. These conditions include no mutation, no migration, no natural selection, random mating, and a large population size.

Therefore, if a population is in Hardy-Weinberg equilibrium, there would be no evolutionary changes, since the allele and genotype frequencies would remain constant over time. This means that options A, B, C, and D are not possible outcomes in a population that is in Hardy-Weinberg equilibrium.

Question 20

Large ears is a rare trait in a mainland population of mice.A few female mice homozygous for very large ears arrive at an island that already contains mice after sneaking onto a boat.This will lead to a population with a higher incidence of big ears than the mainland population because of ________

Accepted Answer

Gene flow occurs when individuals or their gametes move from one population to another, introducing new alleles into the population. In this scenario, the arrival of mice with large ears introduces the alleles for large ears into the island population, potentially increasing the frequency of this trait compared to the mainland population.

Quiz 20: Genes Within Populations

In a small population of cockroaches living in your kitchen,only a few roaches mate in one year.This can lead to random changes in allele frequency in the population through ________

For a gene with two alternative alleles,B and b,the term q² in the Hardy-Weinberg equation represents

For a gene with two alternative alleles,A (with a frequency of p) and B (with a frequency of q) ,the term in the algebraic form of the Hardy-Weinberg equilibrium for the heterozygote genotype frequency is

Female cardinals select male mates in part based on their bright red color.What effect would this have on a cardinal population that was in Hardy-Weinberg equilibrium?

About 80% of the alleles present in thoroughbred horses can be dated back to 31 known ancestors from the late eighteenth century.As a result,one would expect ________

Animals that select mates that are phenotypically similar will have ________ when compared with Hardy-Weinberg predictions.

Some flowering plants cannot self-pollinate which increases their tendency to mate with phenotypically different mates,a process called disassortative mating.What effect would this have on a population in Hardy-Weinberg equilibrium?

Gene flow,defined as the movement of genes from one population to another,can take place by migration,as well as

The observation that most pureblood Native Americans have type O blood is best explained by ________

Certain small towns in the western United States have remained isolated and inbred since their settlement many years ago.Some alleles are more common in these communities as compared to the rest of the population.This effect is known as

Hardy-Weinberg pointed out that the original proportions of the genotypes in a population would remain constant from generation to generation if certain assumptions are met.Which one of the following is not a Hardy-Weinberg condition?

In a forest,trees that get more sunlight grow taller than other nearby trees.This is a form of ________

An island is on the migration route of sea birds.This island also has abundant tree nesting birds that live on the island permanently and are not found on any other island.The tree nesting birds are more likely than the sea birds to be in Hardy-Weinberg equilibrium because:

You spray your kitchen with an insecticide to kill the cockroaches.A few survive and reproduce,producing a large healthy population in a few generations that all have similar genetic backgrounds.This is an example of ________

________ would keep a population in Hardy-Weinberg equilibrium.

Cheetahs have been through a genetic bottleneck; evidence for this is that

Being born with extra fingers on a hand is called polydactyly.This is more common in some populations in North America than others due to ________.

In order for natural selection to occur within a population,certain conditions must be met.One such condition is

If a population was in Hardy-Weinberg equilibrium,then ________ would occur in that population.

Large ears is a rare trait in a mainland population of mice.A few female mice homozygous for very large ears arrive at an island that already contains mice after sneaking onto a boat.This will lead to a population with a higher incidence of big ears than the mainland population because of ________

Quiz 20: Genes Within Populations

In a small population of cockroaches living in your kitchen,only a few roaches mate in one year.This can lead to random changes in allele frequency in the population through ________

For a gene with two alternative alleles,B and b,the term q2 in the Hardy-Weinberg equation represents

For a gene with two alternative alleles,A (with a frequency of p) and B (with a frequency of q) ,the term in the algebraic form of the Hardy-Weinberg equilibrium for the heterozygote genotype frequency is

Female cardinals select male mates in part based on their bright red color.What effect would this have on a cardinal population that was in Hardy-Weinberg equilibrium?

About 80% of the alleles present in thoroughbred horses can be dated back to 31 known ancestors from the late eighteenth century.As a result,one would expect ________

Animals that select mates that are phenotypically similar will have ________ when compared with Hardy-Weinberg predictions.

Some flowering plants cannot self-pollinate which increases their tendency to mate with phenotypically different mates,a process called disassortative mating.What effect would this have on a population in Hardy-Weinberg equilibrium?

Gene flow,defined as the movement of genes from one population to another,can take place by migration,as well as

The observation that most pureblood Native Americans have type O blood is best explained by ________

Certain small towns in the western United States have remained isolated and inbred since their settlement many years ago.Some alleles are more common in these communities as compared to the rest of the population.This effect is known as

Hardy-Weinberg pointed out that the original proportions of the genotypes in a population would remain constant from generation to generation if certain assumptions are met.Which one of the following is not a Hardy-Weinberg condition?

In a forest,trees that get more sunlight grow taller than other nearby trees.This is a form of ________

An island is on the migration route of sea birds.This island also has abundant tree nesting birds that live on the island permanently and are not found on any other island.The tree nesting birds are more likely than the sea birds to be in Hardy-Weinberg equilibrium because:

You spray your kitchen with an insecticide to kill the cockroaches.A few survive and reproduce,producing a large healthy population in a few generations that all have similar genetic backgrounds.This is an example of ________

________ would keep a population in Hardy-Weinberg equilibrium.

Cheetahs have been through a genetic bottleneck; evidence for this is that

Being born with extra fingers on a hand is called polydactyly.This is more common in some populations in North America than others due to ________.

In order for natural selection to occur within a population,certain conditions must be met.One such condition is

If a population was in Hardy-Weinberg equilibrium,then ________ would occur in that population.

Large ears is a rare trait in a mainland population of mice.A few female mice homozygous for very large ears arrive at an island that already contains mice after sneaking onto a boat.This will lead to a population with a higher incidence of big ears than the mainland population because of ________

For a gene with two alternative alleles,B and b,the term q² in the Hardy-Weinberg equation represents