Mutations - learning outcomes/ questions

Question 1

Mutations are changes in the DNA that can result in what?

Answer 1

Mutations are changes in the DNA that can result in no protein or an altered protein being synthesised.

Question 2

Single gene mutations involve what? .

Answer 2

Single gene mutations involve the alteration of a DNA nucleotide sequence as a result of the substitution, insertion or deletion of nucleotides.

Question 3

Name the Nucleotide substitutions.

Answer 3

Nucleotide substitutions — missense, nonsense and splice-site mutations.

Question 4

Missense mutations result in what and is when?

Answer 4

Missense mutations result in one amino acid being changed for another. This may result in a non-functional protein or have little effect on the protein.

Question 5

Nonsense mutations result in a what and is when?

Answer 5

Nonsense mutations result in a premature stop codon being produced which results in a shorter protein.

Question 6

Splice-site mutations result in some what?

Answer 6

Splice-site mutations result in some introns being retained and/or some exons not being included in the mature transcript.

Question 7

Nucleotide insertions or deletions result in what?

Answer 7

Nucleotide insertions or deletions result in frame-shift mutations.

Question 8

Frame-shift mutations cause all of the codons and all of the amino acids after the mutation to be what?

Answer 8

Frame-shift mutations cause all of the codons and all of the amino acids after the mutation to be changed.

Question 9

Frame-shift mutations cause all of the codons and all of the amino acids after the mutation to be changed. What is the big effect of this?

Answer 9

This has a major effect on the structure of the protein produced.

Question 10

Name the Chromosome structure mutations.

Answer 10

Chromosome structure mutations — duplication, deletion, inversion and translocation.

Question 11

Duplication is what?

Answer 11

Duplication is where a section of a chromosome is added from its homologous partner.

Question 12

Deletion is what?

Answer 12

Deletion is where a section of a chromosome is removed.

Question 13

Inversion is what?

Answer 13

Inversion is where a section of chromosome is reversed.

Question 14

Translocation is what?

Answer 14

Translocation is where a section of a chromosome is added to a chromosome, not its homologous partner.

Question 15

The substantial changes in chromosome mutations often make them what?

Answer 15

The substantial changes in chromosome mutations often make them lethal.

Question 16

Duplication allows what to occur in a duplicated gene whilst the original gene can still be expressed to produce its protein.

Answer 16

Duplication allows potential beneficial mutations to occur in a duplicated gene whilst the original gene can still be expressed to produce its protein.