17.2: Evolution as Genetic Change in Populations

Question 1

directional selection

Answer 1

form of natural selection when individuals at one end of a distribution curve have higher fitness than individuals in the middle or at the other end of the curve

Question 2

stabilizing selection

Answer 2

form of natural selection in which individuals near the center of a distribution curve have higher fitness than individuals at either end of the curve

Question 3

disruptive selection

Answer 3

natural selection in which individuals at the upper and lower ends of the curve have higher fitness than individuals near the middle of the curve

Question 4

genetic drift

Answer 4

random change in allele frequency caused by a series of chance occurrences that cause an allele to become more or less common in a population

Question 5

bottleneck effect

Answer 5

a change in allele frequency following a dramatic reduction in the size of a population

Question 6

founder effect

Answer 6

change in allele frequencies as a result of the migration of a small subgroup of a population

Question 7

genetic equlibrium

Answer 7

situation in which allele frequencies in a population remain the same

Question 8

Hardy-Weinburg principle

Answer 8

principle that states that allele frequencies in a population remain constant unless one or more factors cause those frequencies in a population remain constant unless one or more factors cause those frequencies to change

Question 9

sexual selection

Answer 9

when individuals select mates based on heritable traits