KA6 - mutations :) Flashcards
1
Q
What is a mutation?
A
- a change in the DNA where no protein or an altered protein is being synthesised
2
Q
What are single gene mutation examples?
A
- substitution
- insertion
- deletion
OF SINGLE NUCLEOTIDES
3
Q
What is a missense mutation?
A
- 1 amino acid is changed
- results in a non functional protein
- OR has little effect on protein
4
Q
What is a nonsense mutation?
A
- premature stop codon
- results in shorter protein
5
Q
What is a splice-site mutation?
A
- where some introns are retained and some exons are not included in the mature transcript
6
Q
What is a frame-shift mutation?
A
- all of the codons and amino acids after the mutation are changed
- major effect on the structure of the protein produced
7
Q
What are the examples of chromosome mutations?
A
- duplication
- deletion
- inversion
- translocation
8
Q
What is duplication?
A
Where a section of chromosome is added from its homologous partner
9
Q
What is translocation?
A
Where a section of chromosome is added but not from its homologous partner
10
Q
What mutation can possibly be beneficial?
A
duplication! - chromosome
11
Q
Why is duplication helpful?
A
- allows potential beneficial mutations to occur in the duplicated gene
- whilst the original gene can still be expressed to produce its protein
