Question 1

In an equilibrium population

Accepted Answer

In an equilibrium population, allele frequencies remain constant over time if no other evolutionary influences (such as natural selection, gene flow, mutation, or genetic drift) are acting on the population. This concept is central to the Hardy-Weinberg principle.

Question 2

A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy-Weinberg equation, p2 represents the

Accepted Answer

p2 in the Hardy-Weinberg equation represents the proportion of homozygous dominant individuals in a population.

Question 3

A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy-Weinberg equation, q2 represents the

Accepted Answer

In the Hardy-Weinberg equation, q^2 represents the proportion of homozygous recessive individuals in a population.

Question 4

The interaction of genes and environment produces a specific

Accepted Answer

The interaction of genes and the environment specifically produces a phenotype, which is the observable characteristics or traits of an organism.

Question 5

In a very small population of birds, assume 5 out of 20 alleles are the type that codes for blue feathers. What is the allele frequency of the ʺblue feather alleleʺ in this population?

Accepted Answer

The allele frequency is calculated by dividing the number of alleles for a specific trait by the total number of alleles. In this case, 5 out of 20 alleles code for blue feathers, so the frequency is 5/20 = 0.25.

Question 6

Imagine that one of the original four mice that escape from a research lab is blind due to a genetic defect. If the escaped mouse breeds and most of the mice born in subsequent generations are blind from birth, this is most likely a case of

Accepted Answer

The founder effect occurs when a small group from a population establishes a new population, and the genetic traits of the founders are disproportionately represented in the new population. In this scenario, because the population of mice descended from a small number of original mice, including one that was blind due to a genetic defect, and most of the subsequent generations are blind, it indicates that the genetic makeup of the initial small group (founders) has had a significant impact on the traits of the new population. This is characteristic of the founder effect.

Question 7

Within a large population, if no mutations occur, no migration occurs, all matings are random, and each individual has an equal chance of reproducing, which of the following will probably happen?

Accepted Answer

The conditions described are essentially those of the Hardy-Weinberg equilibrium, which states that allele frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. Therefore, no evolution will occur under these conditions.

Question 8

A population is defined as

Accepted Answer

A population refers to all individuals of the same species that are found in a specific geographic area, allowing them to potentially interbreed.

Question 9

Populations of organisms are constantly evolving, which means that they are always

Accepted Answer

Populations of organisms evolve through processes such as natural selection, mutation, gene flow, and genetic drift, leading to changes in their genetic makeup and traits over time. This does not necessarily mean they are improving, becoming more like humans, constantly growing in size, or at equilibrium. Evolution is fundamentally about change.

Question 10

A young male baboon leaves the troop that he was born in and joins a small neighboring troop of small baboons. He quickly rises to become a dominant male. From an evolutionary point of view, what important process has occurred?

Accepted Answer

Gene flow occurs when individuals move between populations, bringing new genetic material into the population they join. This young male baboon moving to a new troop and potentially breeding there introduces his genetic material to the new troop, which is a classic example of gene flow.

Question 11

A population carries two alleles for a trait in which T is dominant and t is recessive. In the Hardy-Weinberg equation, 2pq represents the

Accepted Answer

2pq in the Hardy-Weinberg equation represents the proportion of heterozygous individuals in a population, where p is the frequency of the dominant allele (T) and q is the frequency of the recessive allele (t).

Question 12

Inbreeding is defined as

Accepted Answer

Inbreeding refers to the mating or breeding of individuals that are closely related genetically, leading to a higher chance of offspring inheriting similar genes from both parents.

Question 13

Which of the following can evolve?

Accepted Answer

The answer of Which of the following can evolve?
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Question 14

In the context of evolution, equilibrium means

Accepted Answer

Equilibrium in the context of evolution, particularly when referring to the Hardy-Weinberg equilibrium, means that there is no change in allele frequency within a population over time. This concept assumes no mutation, migration, genetic drift, or selection occurs, allowing allele frequencies to remain constant from one generation to the next.

Question 15

Which of the following can cause evolutionary change in a small population?

Accepted Answer

Genetic drift is a mechanism of evolution that causes random changes in allele frequencies in small populations, leading to evolutionary change.

Question 16

Which of the following is most likely to experience genetic drift?

Accepted Answer

Genetic drift is more likely to occur in small populations where random events can significantly change the frequency of alleles. A population of endangered birds that includes only five individuals is small enough for genetic drift to have a noticeable effect.

Question 17

The allele frequency of a population is the

Accepted Answer

The allele frequency in a population refers to the relative proportion of a given allele among all alleles for a particular gene in the population.

Question 18

Evolution can be defined as

Accepted Answer

The answer of Evolution can be defined as
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Question 19

According to the Hardy-Weinberg principle, if 75% of the alleles in the gene pool are A1 and 25% are A2, what is the proportion of individuals with genotype A1A2 in this population?

Accepted Answer

The Hardy-Weinberg principle can be used to calculate the frequencies of genotypes in a population if the allele frequencies are known. The frequency of A1A2 individuals can be calculated using the formula 2pq, where p is the frequency of one allele (A1 = 0.75) and q is the frequency of the other allele (A2 = 0.25). Thus, 2 * 0.75 * 0.25 = 0.375.

Question 20

The gene pool for a particular population is made up of

Accepted Answer

The gene pool of a population includes all the genes (alleles for all traits) present in that population, not just those for a single trait or in a single individual.

Quiz 16: How Populations Evolve