Mutations Flashcards
What are the types of frameshift mutations?
deletion
addition
duplication
translocation
What is a translocation mutation?
bases become separated from DNA sequence on one chromosome and are inserted into the DNA sequence on another chromosome
What are the types of mutation?
Substitution
Addition
Deletion
Duplication
Inversion
Translocation
What is an inversion mutation?
bases are removed from DNA then rejoin in the same location in reverse order
What are 3 causes of gene mutations?
chemical mutagens
ionising radiation
spontaneous errors
What are 2 examples of chemical mutagens?
- alcohol
- benzene
- tar in tobacco
What are 2 examples of ionising radiation?
- alpha
- beta
- X-rays
- UV
How might a mutation be neutral?
- occurs in non-coding introns
- silent mutation
- change in tertiary structure does not impact the organism
What is a mutation?
a change in the structure or quantity of DNA
Why does changing a base have a big impact?
- impacts primary structure
- difference in the bonds formed and their position
- impacting tertiary structure
- As these are specific it can cause them to become non-functioning
What is a silent mutation?
a mutation that does not change the amino acid sequence, these happen because DNA is degenerate
Why might a mutation not lead to an inactive protein?
- the change in base sequence might code for the same amino acid as before
- because DNA is degenerate
- so tertiary structure is not changed
What are the possible effects of base substitution/base inversion?
- no change as same amino acid is coded for
- different amino acid coded for, could potentially lead to an inactive protein
- stop codon forms, stopping the production of a polypeptide without it being complete
What is a gene mutation?
a change or rearrangement in the order of bases in DNA
What is the impact of a base deletion?
- frame shift left; so triplets from that point onwards are impacted and read differently
- code for different amino acids
- so different primary and tertiary structure
