Module 8- Module 8 - Alteration of the sequence of bases in DNA can alter the structure of proteins Flashcards
What is a mutation?
This is when there is a change to the base nucleotide sequence of DNA
What is substitution deletion?
This is when one or more bases is swapped for another
What is a deletion mutation?
This is when one or more bases are removed causing a frameshift
What is an addition mutation?
This is when one or more bases are added causing a frameshift
What is a duplication mutation?
One or more bases are repeated
What is an inversion mutation?
The DNA of a single gene is cut in 2 place. The cut portion is inverted 180degrees then rejoined to the same place within the gene
Frequently result in a non- functional protein
What is a translocation mutation?
A sequence of bases which is moved from one location in the genome to another. This can be a movement within the same chromosome or a movement to a different chromosome
Why do some mutations not lead to a change in the amino acid sequence?
Some amino acids are degenerate meaning that it doesn’t always cause a evident change
What mutations will have the least impact on an amino acid sequence?
Substitution and inversion
What are mutagenic agents?
These are factors that increase the likelihood of a mutation happening
What are the 4 main examples of a mutagenic agent?
- Ultraviolet radiation
- Ionising radiation
- Chemicals
- Viruses
What are the 3 ways mutagenic agents can increase the rate of mutations?
- Acting as a base
- Altering bases
- Changing the structure of DNA
How does a mutation of human genes that code for tumour suppressor genes cause cancer?
A mutation in a tumour suppressor proteins could cause a change in the DNA base sequence resulting in a change in the tertiary structure of the tumour suppressor proteins resulting in uncontrolled cell division
