exam pack

Question 1

how does sexual reproduction produce variation

Answer 1

fusion of gametes (1 mark)

which results in the mixing of genetic information (1 mark)

Question 2

what is a dominant allele

Answer 2

expressed if just one copy of allele is present

Question 3

explain how the mutation could cause the enzyme not to work

Answer 3

there is a change in the three bases

(mutation) changes the amino acid

(this could) change the protein

(so it) forms a different shape / changed active site

(therefore) the enzyme no longer fits the substrate / carbohydrate

Question 4

explain how a change in one amino acid in an enzyme molecule could stop the enzyme working

Answer 4

a change in the shape (of enzyme) causes a different protein made

active site changed

so substrate does not fit / bind