Question 1

What is the result of a mutation that occurs in somatic cells?

Accepted Answer

Mutations that occur in somatic cells will not be passed along to the organism's offspring, as they only affect the individual and not their reproductive cells. The mutation may be expressed in the individual, but will not be inherited by their offspring.

Question 2

A population in biology refers to a group of organisms in the same geographic area that:

Accepted Answer

A population in biology refers to a group of organisms in the same geographic area that are the same species. This means they can interbreed and produce viable offspring.  Options A, B, D, and E do not accurately describe a population.

Question 3

What kind of mutation has no effect on an organism's ability to survive or reproduce?

Accepted Answer

A neutral mutation is a type of mutation that does not provide any advantage or disadvantage to the organism. Therefore, it has no effect on the ability of the organism to survive or reproduce.

Question 4

Which of the following would be considered an advantageous mutation?

Accepted Answer

An advantageous mutation confers a selective advantage to the organism, meaning it increases its chances of survival and reproduction. Therefore, a mutation that increases an organism's ability to find food would be considered advantageous.

Question 5

Which of the following research questions would a population geneticist be MOST likely to ask?

Accepted Answer

All of these questions are concerned with genetic variability and diversity within species or among different species, which are central topics in population genetics. Population geneticists study the genetic composition of populations and how it changes over time, making all these questions relevant to their research.

Question 6

Genetic variation has two sources-mutation and:

Accepted Answer

While natural selection, genetic drift, non-random mating, and cell division can all affect the distribution of genetic variation within a population, they do not create new genetic variation. Mutation is the only process that introduces new genetic variation into a population, and therefore is the correct answer. Recombination (the shuffling of genetic material during sexual reproduction) can also contribute to genetic variation, but it relies on the existence of pre-existing genetic variation that is being recombined rather than creating new variation itself.

Question 7

Which of the following is a source of genetic variation?

Accepted Answer

Recombination, also known as crossing over, during meiosis is a source of genetic variation. It results in the creation of new combinations of alleles on chromosomes. Bottlenecks, genetic drift, and natural selection can also affect genetic variability, but they do not create new genetic variation like recombination does. Adaptations are a result of natural selection acting on existing genetic variation.

Question 8

As a population geneticist, you find a species of snails with more genetic diversity than humans. What does this mean?

Accepted Answer

Genetic diversity refers to the variety of genotypes within a population, and is often used as a measure of the gene pool's richness. The statement suggests that the snail has more genetic diversity than humans, which means that there are more variations in gene sequences, allele frequencies, or other genetic features that contribute to the species' adaptability to changing environments. Therefore, option B is the most accurate answer. The other options can be false or partially true, but they don't provide a satisfactory explanation of the observed phenomenon.

Question 9

Interbreeding groups of organisms of the same species living in the same geographical area are called:

Accepted Answer

Interbreeding groups of organisms of the same species living in the same geographical area are called populations. Gene pools refer to the total set of genes (alleles) found in a population. Fixed groups and randomly mating groups are not terms commonly used in population biology.

Question 10

Which of the following may be a characteristic of a beneficial mutation?

Accepted Answer

A beneficial mutation would provide an advantage, increasing the likelihood of successful reproduction and passing on the mutation to future generations. Decreasing lifetime reproductive output or decreasing fitness would be detrimental, while having no effect on phenotype would not be considered beneficial, as it would not have any impact on the organism's survival or reproductive success.

Question 11

Genetic variation in a population refers to which of the following?

Accepted Answer

Genetic variation in a population refers to the presence of different forms of a gene (alleles) within a gene pool. This variation can influence traits in individuals and contribute to the evolution of a species over time. The other choices are not accurate descriptions of genetic variation.

Question 12

All the alleles present in all individuals in a species are referred to as the _____ of that species.

Accepted Answer

The gene pool refers to all the alleles present in a given population or species. It includes all possible versions of all genes present in the population. Allele frequency and genotype frequency are both measures of the proportion of alleles or genotypes in a population, but they do not encompass all the alleles present in the species as a whole. Genotype and phenotype are specific terms referring to the genetic makeup and observable traits of an individual, respectively, and do not refer to the entire set of alleles in a species.

Question 13

Humans are considered to be the most genetically diverse organisms on Earth, and possess considerably more genetic variation compared to any insect or avian species.

Accepted Answer

Humans are actually less genetically diverse than many other species, including some insects and avian species. This is partly because humans went through a population bottleneck in the past, reducing our genetic diversity.

Question 14

Why is genetic variation critical for evolution?

Accepted Answer

Genetic variation is the source material for natural selection. Natural selection acts on the genetic variation within a population, favoring individuals with traits that are better suited to their environment. This leads to the evolution of new species and the adaptation of existing species to changing environments.

Question 15

What is one reason why many mutations may be deleterious?

Accepted Answer

Mutations that change the primary structure of a protein can have deleterious effects because the protein may no longer be able to perform its function properly. This can lead to a variety of issues in organisms, such as developmental abnormalities or disease.

Question 16

Consider a population of killer whales. The gene pool of this population would only contain alleles harboring beneficial or neutral mutations, as deleterious mutations are efficiently eliminated from the gene pool of a species.

Accepted Answer

While deleterious mutations are indeed eliminated from the gene pool of a species, they can still persist at low frequencies through various mechanisms such as genetic drift or heterozygote advantage. Therefore, the gene pool of a population can contain alleles harboring deleterious mutations in addition to beneficial or neutral ones.

Question 17

From an evolutionary perspective, germ-line mutations are more significant than somatic mutations. This is because:

Accepted Answer

Germ-line mutations are more significant from an evolutionary perspective because they can be passed on to an individual's descendants, affecting future generations, whereas somatic mutations typically affect only a limited number of cells and do not get passed on to offspring.

Question 18

A gene pool is comprised of what?

Accepted Answer

A gene pool consists of all the alleles present in a population, representing the genetic diversity available for evolution and adaptation.

Question 19

Mutations in skin cells that result in melanoma are considered _____ mutations; a mutation that can be passed on from parent to offspring are referred to as a _____ mutation.

Accepted Answer

Mutations in skin cells that result in melanoma are somatic mutations, as they occur in non-reproductive cells and do not affect offspring. Mutations that can be passed on from parent to offspring are germ-line mutations.

Question 20

In genetics, two organisms are part of the same population if:

Accepted Answer

Two organisms are part of the same population if they are the same species and are in the same geographic area. Being part of the same population means that they have the potential to interbreed and share genes, which is important for understanding the genetic makeup and evolution of that population. Choice A is not sufficient because two different species could be in the same geographic area without being part of the same population. Choice B is not specific enough, as organisms can be from different gene pools even within the same population. Choice C is not a reliable indicator of population membership as different genotypes can produce the same phenotype. Choice D is not sufficient because organisms from different populations could still inhabit the same geographic area.

Quiz 21: Evolution: How Genotypes and Phenotypes Change Over Time