Lecture 5: More about Evolutionary Processes

Question 1

Name two types of non-random mating.

Answer 1

1. Selfing
2. Inbreeding

Question 2

What does inbreeding increase? How is this affected when an allele is recessive lethal or recessive deleterious?

Answer 2

Homozygosity. This causes change in allele frequencies because there is a higher chance of death due to the recessive allele frequency increase.

Question 3

What is genetic drift?

Answer 3

Genetic drift is a change in allele frequencies due to chance.
1. Occurs in every population
2. Has a bigger effect in small populations
3. Can lead to changes in allele frequencies including loss of an allele
4. is random with respect to fitness

Question 4

What is gene flow?

Answer 4

Gene flow is the movement of alleles from one population to another.

Question 5

What is a mutation and how is it related to heritable variation in a population?

What is a neutral mutation?

Answer 5

Mutations are changes in DNA that often result froma mistake during DNA replication. They are heritable (passed on to offspring).

A neutral mutation is a mutation that still changes the DNA but has no visible effect on an organism’s fitness.