Genetic Diversity

Question 1

Define Genetic Diversity

Answer 1

Difference in DNA/base sequence/difference in alleles

Question 2

Define genetic bottleneck

Answer 2

• Drop in population/many killed/only single female left

- Reduced/low genetic variation/diversity/reduction in variety of alleles/smaller gene pool

Question 3

Why is the fertility of cheetahs low?

Answer 3

• Have a higher proportion of abnormal sperm cells
• Mutations affecting sperm cell or production
• Errors during meiosis
• Inbreeding/closely related cheetahs breed
• High chance of inheriting allele/high frequency of allele (in population)

Question 4

How can a mutation lead to the production of a protein with a missing amino acid?

Answer 4

Loss of 3 bases/triplet

Question 5

Define selective breeding

Answer 5

(Humans breed) organisms with certain/chosen characteristics/alleles

Question 6

Problems with selective breeding

Answer 6

• Inbreeding/breed closely related organisms
• (So higher probability of) mutations bing passed on/recessive alleles being expressed
• Reduced genetic variation/diversity/less variety of alleles
• So can be killed by/susceptible to the same disease/environmental change

Question 7

Name some processes that lead to reduction of genetic diversity in a population of organisms

Answer 7

• Reduced number of different alleles/reduced gene pool
• Founder effect - a few individuals form colonies and become isolated
• (Genetic) bottleneck - significant fall in size of population
• Selective breeding/artificial selection - organisms used for specific characteristics/phenotypes