Chapter 23 Vocabulary

Question 1

Genetic drift

Answer 1

A process in which chance events cause unpredictable fluctuations in allele frequencies from one generation to the next. Effects of genetic drift are most pronounced in small populations

Question 2

Gene pool

Answer 2

The aggregate of all copies of every type of allele at all loci in every individual in a population. The term is also used in a more restricted sense as the aggregate of alleles for just one or a few loci in a population

Question 3

Founder Effect

Answer 3

Genetic drift that occurs when a few individuals become isolated from a larger population and form a new population whose gene pool composition is not reflective of that of the original population

Question 4

Bottleneck effect

Answer 4

Genetic drift that occurs when the size of a population is reduced, as by a natural disaster or human actions. Typically, the surviving population is no longer genetically representative of the original population.

Question 5

average heterozygosity

Answer 5

The percentage, on average, of a population’s loci that are heterozygous in members of the population.

Question 6

cline

Answer 6

A graded change in a character along a geographic axis.

Question 7

gene flow

Answer 7

The transfer of alleles from one population to another, resulting from the movement of fertile individuals or their gametes.