19.1 Muattions And Variations

Question 1

What is a substitution change in DNA?

Give an example

Answer 1

One nucleotide is exchanged for another

Sickle cell anaemia

Question 2

What is a insertion change in DNA?

Give an example

Answer 2

An extra nucleotide (or more than one) is placed in the DNA sequence
Huntington’s disease

Question 3

What is a deletion change in DNA?

Give an example

Answer 3

A nucleotide (or more than one) is removed from the DNA sequence
Cystic fribrosis

Question 4

What is a silent mutation and what effect does it have?

Answer 4

A motion that could be in a non-coding region
or
A mutation that produces a new codon that codes for the same amino acid (because of the degenerate code)

No effect