Gene Mutations

?
  • Created by: Esme.B
  • Created on: 09-01-18 13:56
Mutation
a change in the sequence of the nucleotide bases of DNA
1 of 18
Two types of mutation?
Point mutation + Insertion/ deletion
2 of 18
Point mutation?
One base pair replaces (is substituted for) another.
3 of 18
3 types of point mutation?
Silent + Missense + nonsense
4 of 18
Silent mutation?
Change in base triplet but still codes for the sam amino acid
5 of 18
Missense mutation?
Change in base triplet but changes the animo acid sequence - sickle cell anaemia
6 of 18
Nonsense mutation?
Nonsense is known as a Stop codon means the protein won’t be fully built and won’t function properly- Duchenne muscular Dystrophy
7 of 18
Insertion or deletion mutation?
Nucleotides are inserted or deleted from length of DNA, this causes a frameshift
8 of 18
Frameshift?
Framing error occurs due to insertions or deletions. - always causes large changes.means that the polypeptide produced is useless or has a stop code half way through.
9 of 18
Example of an Insertion mutation?
Huntington's disease
10 of 18
Example of a deletion mutation?
Cystic fibrosis
11 of 18
List 2 mutations which are un-harmful?
1). Differently shaped ear lobes. 2). Inability to smell certain flowers i.e honeysuckle
12 of 18
Chromosome Mutation?
mutation may cause a change Chromosome Mutation = in the structure or number of whole chromosomes in cells.
13 of 18
Mutagenic?
Environmental Factorssignificantly increase the chance of a mutation occuring.
14 of 18
List 3 examples of Environmental factors?
X­rays and gamma rays, Ultra Violet Radiation + smoking
15 of 18
List 3 features , that makes DNA structure stable and fairly resistant to mutations ?
Covalent bonds between nucleotides,Found in nucleus,Hydrogen bonds between base pairs + double Helix
16 of 18
Explain how the degenerate nature of the genetic code reduces the effects of point mutations.
In some cases a change to the triplet code does not change the amino acid coded for at that point in the polypeptide chain.
17 of 18
Sometimes during translation, a tRNA molecule may combine with the wrong amino acid. How may this affect the protein being assembled at a ribosome?
An incorrect amino acid would be inserted into the polypeptide chain, even though there is no point mutation in the DNA/gene.
18 of 18

Other cards in this set

Card 2

Front

Two types of mutation?

Back

Point mutation + Insertion/ deletion

Card 3

Front

Point mutation?

Back

Preview of the front of card 3

Card 4

Front

3 types of point mutation?

Back

Preview of the front of card 4

Card 5

Front

Silent mutation?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all Gene Mutation resources »