Question 1

Natural selection determines how a species

Accepted Answer

D

Question 2

The idea that organisms with genetically determined characteristics that make them better suited for the environment will have more surviving offspring is

Accepted Answer

The theory of natural selection, proposed by Charles Darwin, suggests that organisms with traits that are advantageous for survival in their environment are more likely to reproduce and pass those traits on to the next generation.

Question 3

Which of the following is a common selective agent for natural selection?

Accepted Answer

Competition for food and other resources is a common selective agent for natural selection because it directly affects an organism's ability to survive and reproduce. Organisms that are better adapted to compete for limited resources are more likely to pass on their genes to the next generation.

Question 4

Which of these factors would be involved in maintaining a constant gene frequency in a population?

Accepted Answer

Lack of migration helps maintain a constant gene frequency in a population by preventing the addition or loss of alleles, which could otherwise alter the genetic makeup of the population.

Question 5

Spontaneous mutations, which will be passed to offspring, can occur in the cell's

Accepted Answer

Spontaneous mutations that will be passed to offspring occur in the cell's DNA, as it is the genetic material inherited by offspring. mRNA and tRNA are involved in protein synthesis and do not transmit genetic information to offspring.

Question 6

In order for the frequency of a particular allele in a population to increase,

Accepted Answer

All of these statements contribute to the increase in frequency of a particular allele within a population. Selection for an allele means it confers some advantage that leads to better survival or reproduction. Those with the allele being better reproducers directly increases the allele's frequency in the next generation. Similarly, if individuals without the allele compete less effectively, those with the allele are more likely to survive and reproduce, again increasing the allele's frequency.

Question 7

In order to maintain somewhat constant genetic frequencies, there must be

Accepted Answer

All of these conditions are necessary to maintain constant genetic frequencies in a population, according to the Hardy-Weinberg principle. A large population size prevents genetic drift, low migration and mutation rates minimize changes in allele frequencies, and random mating ensures that allele combinations occur by chance, not by selection.

Question 8

Which of the following would be an example of sexual selection?

Accepted Answer

Sexual selection refers to the evolutionary pressures that relate to an organism's ability to obtain a mate. Females avoiding aggressive males is an example of sexual selection because it involves mate choice based on behavioral traits.

Question 9

When new alleles enter a gene pool, the frequency of the new allele

Accepted Answer

The introduction of new alleles into a gene pool can occur through migration, a process known as gene flow. When individuals from one population move to another and breed, they can introduce new genetic variants into the receiving population's gene pool.

Question 10

The gene frequencies of a population can be expected to change if

Accepted Answer

Gene frequencies in a population are more likely to change in small populations due to genetic drift, which is a random fluctuation in allele frequencies that occurs by chance.

Question 11

Natural selection may result in

Accepted Answer

Natural selection leads to the retention of favorable genes in a population because individuals with advantageous traits are more likely to survive and reproduce, passing those traits on to the next generation. Mutations are random changes in DNA, and the introduction of new genes into a population typically occurs through mechanisms like gene flow, not directly through natural selection.

Question 12

Gene frequencies will NOT change in a population if certain conditions are met, such as if

Accepted Answer

The conditions listed in options A, B, and C are part of the Hardy-Weinberg equilibrium principle, which states that gene frequencies in a population will remain constant from generation to generation if these conditions are met. This includes random mating, no migration (gene flow), and no mutation, among others.

Question 13

____ is NOT a condition of the Hardy-Weinberg concept.

Accepted Answer

The Hardy-Weinberg principle assumes a large population size to apply its conditions for a population to be in genetic equilibrium. A small population size can lead to genetic drift, which violates the Hardy-Weinberg equilibrium conditions.

Question 14

An organism's fitness is measured by

Accepted Answer

Fitness in evolutionary biology is defined by an organism's ability to survive and reproduce, thus passing on its genes to the next generation. The number of offspring an organism has is a direct measure of its reproductive success, making choice A correct. Choices B and C are factors that can influence fitness but are not direct measures of it.

Question 15

A complete set of genes of an individual in a population is referred to as a

Accepted Answer

A genome is the complete set of genes or genetic material present in a cell or organism.

Question 16

Which is true with regard to the Hardy-Weinberg concept?

Accepted Answer

The Hardy-Weinberg equilibrium assumes no mutation, migration, selection, or genetic drift, and a large population size. Mutation disrupts this equilibrium.

Question 17

There is a population of giraffes. Some have short necks, some have medium-length necks, and some have long necks. If the short-necked individuals are regularly eliminated from the population, this would be an example of

Accepted Answer

Directional selection occurs when natural selection favors one extreme of continuous variation over the other, leading to a shift in the population's phenotypic distribution. In this case, eliminating short-necked giraffes would favor those with longer necks, shifting the population towards longer neck lengths over time.

Question 18

Which of the following traits would NOT affect the genetic diversity of a specific population?

Accepted Answer

Removing the tails of sheep for several generations is a physical alteration and does not affect the genetic makeup or genetic diversity of the population. Genetic diversity is influenced by genetic variations within a population, and physical changes, such as tail docking, do not alter the genes responsible for traits in offspring.

Question 19

Which of the following would be a selecting agent?

Accepted Answer

A selecting agent is an environmental factor that causes differential survival and reproduction, such as the fungus causing Dutch elm disease.

Question 20

If a bacterium with the ability to survive the effects of an antibiotic "pops up" in a population, it most likely

Accepted Answer

Spontaneous mutation is a common mechanism by which bacteria acquire resistance to antibiotics. These mutations can occur randomly in the bacterial DNA, and if they confer an advantage in the presence of an antibiotic, the mutated bacteria can survive and reproduce more than those without the mutation.

Quiz 13: Evolution and Natural Selection