Question 1

The introduction of a small population onto an island that results in a different gene pool from the original source is explained by

Accepted Answer

The founder effect occurs when a small group of individuals becomes isolated from a larger population, leading to a new population with a different gene pool than the original source.

Question 2

All of the following are components of Darwin's principle of natural selection EXCEPT that

Accepted Answer

Darwin's principle of natural selection does not include the production of new alleles through mutation; it focuses on variation, inheritance, overproduction of offspring, and differential survival and reproduction.

Question 3

What accounts for the fact that polydactylism is prevalent and Tay-Sachs disease virtually absent in one human population in the United States, while Tay-Sachs disease is prevalent and polydactylism virtually absent in another?

Accepted Answer

There is little gene flow between the two populations, leading to distinct genetic traits being more prevalent in each due to limited mixing of genetic material.

Question 4

An insect that exhibits resistance to a pesticide

Accepted Answer

Insects that exhibit resistance to a pesticide typically inherit genes that confer resistance from their ancestors, which survived previous exposures to the pesticide. This is a result of natural selection, where resistant individuals survive and reproduce, passing on the resistance genes to their offspring.

Question 5

Successful mating may occur only between members of the same

Accepted Answer

Successful mating typically occurs between members of the same species, as they share compatible genetic and reproductive characteristics necessary for producing viable offspring.

Question 6

The process that probably accounts for most changes in the mix of alleles in a gene pool is

Accepted Answer

The answer of The process that probably accounts for most...

Question 7

The influence of genetic drift on allele frequencies increases as

Accepted Answer

Genetic drift is the random fluctuations of allele frequencies in a population due to chance events, and it has a greater impact on smaller populations. In larger populations, genetic drift may occur, but it is not as strong and may be counteracted by other forces such as natural selection. Therefore, as population size decreases, genetic drift becomes more influential on allele frequencies.

Question 8

Which of the following statements is false?

Accepted Answer

Not all mutations are harmful; some can be beneficial, neutral, or play a role in evolution.

Question 9

When DDT was first introduced, insects were very susceptible to it. The development of resistance to DDT by insects was the result of

Accepted Answer

Resistance to DDT in insects developed due to natural selection of forms that expressed genes for resistance. Over time, insects with genetic variations that allowed them to survive exposure to DDT were more likely to survive and reproduce, passing on their resistant genes to their offspring. This led to an increase in the number of resistant insects and a decrease in the effectiveness of DDT as an insecticide.

Question 10

The only taxonomic category in which evolution can occur is the

Accepted Answer

Evolution occurs within a species, as individuals within a species acquire new traits that are passed on to their offspring.

Question 11

Introduction of previously nonexistent genes into a population may be accomplished by

Accepted Answer

Mutation is the process that introduces new genetic variations or previously nonexistent genes into a population.

Question 12

Although there are as many starlings in North America as there are in Europe, genetic variability in the North American population is reduced relative to that in Europe because

Accepted Answer

The North American starling population originated from a small group of individuals introduced from Europe, leading to reduced genetic variability due to the founder effect.

Question 13

The evolutionary force that operates primarily through chance is

Accepted Answer

Genetic drift is the evolutionary force that operates primarily through chance. It is the random change in the frequency of alleles in a population due to random sampling.

Question 14

Organisms "X" and "Y" are suspected to be the same species. Which of the following will provide the ultimate proof?

Accepted Answer

Interbreeding and producing fertile offspring is the ultimate proof that two organisms belong to the same species.

Question 15

The trait of connected earlobes is considered a

Accepted Answer

Connected earlobes are generally considered a neutral trait as they do not provide any significant advantage or disadvantage to an individual's survival or reproduction.

Question 16

New alleles arise by

Accepted Answer

New alleles can only arise by mutations, which are random changes in the genetic code. Migration, genetic drift, random mating, and independent assortment can affect the frequency of existing alleles, but they do not create new ones.

Question 17

New alleles that appear by mutation

Accepted Answer

New alleles that appear by mutation are seldom advantageous or disadvantageous in themselves and either have or lack survival value only in the context of their environment.

Question 18

The trend in which organisms come to have characteristics that suit them to conditions in a particular environment is called

Accepted Answer

Adaptation is the process by which organisms develop traits that enhance their survival and reproduction in specific environments.

Question 19

One part of Darwin's theory is that individuals with certain traits have an increased competitive edge. The source of these traits in individuals is due to

Accepted Answer

Darwin's theory of natural selection suggests that advantageous traits are inherited from birth, giving individuals a competitive edge in survival and reproduction.

Question 20

Natural selection is best summarized as

Accepted Answer

Natural selection refers to the process by which specific traits that enhance survival and reproduction in a given environment become more common in a population over time. Therefore, the key feature of natural selection is the difference in survival and reproduction among individuals within a population.

Quiz 23: Principles of Evolution