9A The gene pool

Question 1

Outline the steps that result in animals developing new agents

Answer 1

1. There is a variation within the population. (Due to new agent introduced to the population)
2. A new selection agent is introduced
3. Fit individuals reproduce
4. Change in population OVER MANY GENERATIONS

Question 2

List the Mutations (5)

Answer 2

MISSENCE MUTATION substitution of a single nucleotide which changes the affected codon, leading to the production of a different amino acid

SILENT MUTATION substitution of a single nucleotide which does not lead to a change in the amino acid sequence

NONSENSE MUTATION substitution of a single nucleotide leading to the production of a premature stop codon

FRAMESHIFT MUTATION insertion or deletion of nucleotides affecting every codon from the point of mutation onwards

BLOCK MUTATION mutations that affect large amounts of DNA or entire genes

Question 3

What are complete and partial

Answer 3

Complete selection against a phenotype occurs when an individual with a specific phenotype cannot reproduce due to sterility or death reproduction

Partial selection against a phenotype occurs when an individual with a specific phenotype produces fewer than average offspring

Answer 4

Adaptive radiated through divergent evolution due to selection pressures in differen environments over many generations.