GI: Genetic Diversity and Natural Selection

Question 1

Lots of different alleles means what for genetic diversity?

Answer 1

High genetic diversity.

Question 2

Genetic diversity

Answer 2

Number of differnet alleles of genes in a species or population.

Question 3

How is genetic diversity within a population increased?

Answer 3

• Mutations in the DNA - forming new alleles.
• Different alleles being introduced into a population when individuals from anotehr population migrate into them and reproduce - gene flow.

Question 4

What allows natural selection to occur?

Answer 4

Genetic diversity.

Question 5

Genetic bottleneck

Answer 5

An event that causes a big reduction in a population

Question 6

How does a genetic bottleneck reduce genetic diversity?

Answer 6

• Reduces number of different alleles in gene pool

Question 7

Founder effect

Answer 7

A few organisms from a population start a new colony and there is only a small number of different alleles in the initial gene pool.

Question 8

Why might the founder effect occur?

Answer 8

Migration leading to geographical separation

New colony is separated from original population because of eg. religion

Question 9

What does natural selection increase?

Answer 9

Advantageous alleles in a population

Question 10

Describe the process of natural selection:

Answer 10

• Differential reproductive success means some individuals have an allele which increases chance of survival
• Greater proportion of next generation inherits beneficial allele
• Frequency of beneficial allele increases from generation to generation.

Question 11

What are the 3 types of adaptations?

Answer 11

Behavioural

Physiological

Anatomical

Question 12

Behavioural adaptations

Answer 12

Ways an organism acts increases chance of S+R

Question 13

Physiological adaptations

Answer 13

Processes inside an organism that increases chances of S+R

Question 14

Anatomical adaptations

Answer 14

Structural features of organism that increases chances of S+R