Population Genetics

Question 1

Polydactylism occurs _______.a.only in catsb.only in humansc.in less than one in 1000 childrend.more commonly in certain populations, such as the Amish.

Revolt · Accepted Answer

D

Question 2

According to the theory of island biogeography, those islands that are further isolated from the mainland and other islands would be expected to have _______.a.more speciesb.fewer speciesc.more genetic variationd.more immigration to the island

Revolt · Accepted Answer

B

Question 3

How do natural disasters contribute to genetic drift?

Revolt · Accepted Answer

Genetic drift occurs when random events, such as natural disasters, reduce a species’ population. This reduction in population size is often accompanied by a redistribution of the frequency of the expression of certain genes based on what genes the surviving organisms possess.

Question 4

After hunting by European settlers, the bison population of 60 million was reduced to _______ of its original size.a.1 : 60b.1 : 600c.1 : 6,000d.1 : 60,000

Revolt · Accepted Answer

D

Question 5

Which of the following has not resulted in the decline of cheetah populations?a.population bottleneckb.overhuntingc.habitat destructiond.large genetic diversity

Revolt · Accepted Answer

D

Question 6

Bottleneck events lead to _______.a.population growthb.an increase in inbreedingc.an enrichment of dominant genetic traitsd.a reduced rate of species mutation

Revolt · Accepted Answer

B

Question 7

Explain how the Amish are an example of the founder effect.

Revolt · Accepted Answer

The Amish population was established by a small number of individuals whose genetic diversity did not exactly match that of the distribution of genes in the general population. As a result, certain rare traits became more commonly expressed in the Amish population as it grew due to their overrepresentation in the founding gene pool of the population.

Question 8

Explain how a bottleneck event can enrich recessive traits in the genetics of a population.

Revolt · Accepted Answer

A bottleneck event severely reduces the fraction of a species able to pass on their genes to offspring. Any once rare recessive traits present in the surviving breeding population are passed to a larger fraction of the total population of offspring, thereby enriching those recessive traits in the total gene pool.

Question 9

Explain why a population of Mouflon in the Indian Ocean descended from only two individual that had not experienced a loss of genetic diversity was so surprising to scientists.

Revolt · Accepted Answer

When populations are dramatically reduced in size, the theory of genetic drift suggests that a loss of genetic diversity should be expected. In the case of the Mouflon, however, no such loss in diversity was observed. This result was extremely surprising to scientists because it meant that the theory of genetic drift does not always hold true.

Question 10

Explain why the crossbreeding of bison and cattle is both a benefit and hindrance to conservation efforts aimed at protecting bison genetic diversity.

Revolt · Accepted Answer

While the bison gene pool is currently much healthier than that of the cheetah, only one herd among the 4% of all protected bison herds has no known cattle ancestry. Cattle ancestry has helped boost the total population of bison and has increased such herds’ genetic diversity, but those herds do not help protect the bison’s original gene pool.

Population Genetics Answers

More from this Course

TRY EDGENUITY HACKS