Mutations =)

Question 1

Define the term mutagenic agent. (1)

Answer 1

factor that increases rate of mutations.

Question 2

Genetic variation within a species is increased during meiosis by crossing over and the independent segregation of homologous chromosomes.
Apart from mutation, explain one other way genetic variation within a species is increased. (2)

Answer 2

• random fusion of gametes/ fertilisation
• new allele combinations

Question 3

State what is meant by gene mutation. (1)

Answer 3

change in DNA base sequence

Question 4

People with cystic fibrosis produce defective CFTR protein which is missing one amino acid from its structure.
Which type of gene mutation produced the cystic fibrosis allele?
Explain your answer. (2)

Answer 4

• deletion of 3 bases
• substitution would change a.a.