Topic 13 - Forces that drive evolution change allele frequency

Question 1

Gene Pool

Answer 1

The aggregate of all copies of every type of allele at all loci in every individual in a population.

Question 2

Allele Frequency

Answer 2

The rate of occurrence of a specific allele within a population.

Question 3

Allele Loss

Answer 3

When an allele is lost from the gene pool.

Often occurs via the bottleneck effect.

Question 4

Allele Fixation

Answer 4

Whereby one allele is lost from the gene pool which initially had multiple alleles, but now only has one remaining.

Question 5

Genotype Frequency

Answer 5

The rate at which genotypes appear in a population.

Question 6

Hardy-Weinberg Equilibrium

Answer 6

The state of a population in which frequencies of alleles and genotypes remain constant from generation to generation, provided that only Mendelian segregation and recombination of alleles are at work.

Question 7

Interbreeding

Answer 7

The production of offspring from mating or breeding of individuals or organisms that are closely related genetically.

Question 8

Assortive Mating

Answer 8

Non-random mating pattern in which individuals with similar genotopes and/or phenotypes mate with one another more frequently than would be expected with random mating.

Question 9

Sexual Selection

Answer 9

A form of natural selection in which individuals with certain inherited characteristics are more likely than other individuals to obtain mates.

Question 10

Sexual Dimorphism

Answer 10

Differences between secondary sex characteristics of males or females of the same species.

Question 11

Genetic Drift

Answer 11

The change in the frequency of a gene variant in a population due to random sampling of organisms.

Question 12

Population Bottleneck

Answer 12

The reduction in size due to a sudden change in the environment that results in a lower genetic diversity to random chance.

Question 13

Founder Effect

Answer 13

When a few individuals become isolated from a larger population and the small group establishes a new population who gene pool differ from their originating gene pool.

Question 14

Population

Answer 14

A collection of interbreeding organisms of a particular species .

Question 15

What are the four postulates of natural selection?

Answer 15

1) Individuals in a population will vary.
2) The variation is heritable.
3) More offspring are produced than can survive.
4) Individuals differ in their production of offspring.

Question 16

Describe the conditions for Hardy Weinberg equilibrium.

Answer 16

1) A large breeding population.
2) Random mating.
3) No change in allelic frequency due to mutations.
4) No immigration or emigration.
5) No natural selection.