Lecture 6

Question 1

What is a gene?

Answer 1

A combo of two alleles

Question 2

Evolution equals?

Answer 2

Change in allele frequency in a population between gens

Question 3

4 factors that affect frequency

Answer 3

1. Natural selection
2. Gene flow
3. Mutation
4. Genetic drift

Question 4

Fitness?

Answer 4

Extent to which individual’s genotype is represented in the next gen

Question 5

What is directional selection?

Answer 5

When one extreme phenotype is favored

Question 6

What is disruptive selection?

Answer 6

When both extreme phenotypes are favored (polymorphism)

Question 7

What is stabilizing selection?

Answer 7

Intermediate/common phenotype favored

Question 8

Which out of the three selections has a decrease in variance as a result of the mean staying static?

Answer 8

Stabilizing

Question 9

Mutations?

Answer 9

Change in DNA either through structural damage or error in replication

Question 10

Gene flow?

Answer 10

Transfer of genes (alleles) between populations (migration)

Question 11

Gene flow also?

Answer 11

Ups variation within population

Downs variation between populations

Question 12

Genetic drift?

Answer 12

Change in allele frequency due to chance (impact is greater in smaller population)

Question 13

Founder effect?

Answer 13

New population is established by a few colonizers

Question 14

Bottleneck effect?

Answer 14

Few survive, and these are the only few that reproduce in the next gen

Question 15

Negative frequency-dependent selection?

Answer 15

when rare phenotype has advantage