Gene Mutations

Question 1

DNA Mutation

Answer 1

A change in the amount or structure of DNA

Question 2

Gene or Point Mutation

Answer 2

A change in the base sequence of a gene which can cause a change in the polypeptide chain. It is caused by errors that occur during DNA replication

Question 3

Nonsense Mutation

Answer 3

Substitution point mutation - results in a stop codon being coded for, preventing the rest of the polypeptide chain being produced

Question 4

Missense Mutation

Answer 4

Substitution point mutation - results in a different amino acid being coded for potentially affecting the structure and function of the polypeptide chain

Question 5

Silent Mutation

Answer 5

Substitution point mutation - results in the same amino acid being coded for meaning there is no change in the polypeptide produced

Question 6

Deletion

Answer 6

Frameshift point mutation - alters the ‘reading frame’ of the gene downstream of the mutation causing a different sequence of amino acids to be coded for

Question 7

Mutagenic Agents

Answer 7

Disrupt the structure of DNA or interfere with transcription; examples include UV radiation and harmful chemicals