Section 4

Question 1

What could change allele frequencies? If it disrupts the Hardy-Weinberg equilibrium, what can it cause?

Answer 1

• Mutations
• Restricted population
• Non-random mating
• Individuals enters and leave the population
• Natural selection
  Evolution

Question 2

What are the factors that can cause evolution?

Answer 2

1. Natural selection
2. Mutation
3. Gene flow
4. Genetic drift
5. Non-random mating

Question 3

What is natural selection?

Question 4

Why mutations can cause a population to evolve?

Answer 4

If someone has a mutation and is not adapted to survive, they will die and won’t pass dows their mutation.

Question 5

What is gene flow and how can it causes evolution?

Answer 5

Gene flow is the movement of individuals in or out of the population.

individuals go somewhere where there’s an already established population, and begin a new population.
-> It changes alleles frequencies. (Pop. 1 characteristics & Pop. 2 characteristics get mixed)

Question 6

What is genetic drift ? What are the two kinds of genetic drift?

Answer 6

It is the effect of chance events on allele frequencies on a population (ex: natural disasters)

• Population bottleneck. When a chance event eliminates many individuals at random from the pop. in a short period of time.
  -> new pop. will resemble the survivors, not the originla population
• The founder effect. When few individuals start a new pop. in a new area due to some chance event.
  -> new pop. will resemble the founders. not the original population that the founders came from.

Question 7

What is non-random mating? What is it doing to a population?

Answer 7

When mates are not chosen randomly in the pop.
-> preference for the same phenotypes (assortative mating), Limited mate choice due to isolation.

It slowly lead to certain genotypes to be more frequent.

It can have a big impact on allele frequencies when combines when combin