Mutations and Gene Pools

Question 1

What is a mutation?

Answer 1

• changes in the DNA that can occur spontaneously or due to exposure to a mutagen such as ionising radiation.
• they affect a single gene (gene mutation) or more than one gene (chromosomal mutation)

Question 2

What can mutations be classified as?

Answer 2

• Cause
• Heritability
• Effect
• Extent
• Change in DNA

CHEEC

Question 3

What are the effects of a mutation?

Answer 3

• Missense mutations: causes a change in the amino acid and therefore in the protein produced.
• Nonsense mutations: changes the base sequence to the code to STOP, and protein synthesis will be halted.
• Neutral mutations: causes a change in an amino acid, but does not change the overall structure of the protein.
• Silent mutations: do not cause any change in the amino acid, as there are multiple codons that code for the same amino acid.

Question 4

What are the point mutations or changes on the site of DNA

Answer 4

• insertion — a new nucleotide is added to the DNA strand
• subsititution — a new nucleotide replaces the original one, with a different base.
• deletion — a nucleotide is removed from the strand of DNA

Question 5

What are the causes for a mutation?

Answer 5

induced mutations: when the organism is exposed to a mutagen in their DNA
random mutations: when there is a random biological error in the sequence of the organism’s DNA.