1.6 Flashcards
Mutations are
Changes in DNA that can result in no protein or an altered protein being produced
Single gene mutation involves
The changing of a DNA nucleotide sequence
Insertion involves
The addition of a nucleotide
Deletion involves
The removal of a nucleotide
Deletion and insertion are
Frameshift mutations
Frameshift mutations mean
The sequence of every amino acid after the mutation will cause every codon to be different.
Every codon being different means
Every amino acid will be different so the protein will either not work or be different
Substitution involves
The replacing of a nucleotide
Replacing a nucleotide means
Only one amino acid is affected
Substitution mutations result in
Different effects on a protein
Types of substitution mutations
- Missense
- Nonsense
- Splice-site
Missense mutation is
One amino acid being changed for another
Missense mutation results in
Either little effect on the final protein or may change the protein to make it non functional
Nonsense mutation is
A premature stop codon being produced
Nonsense mutation results in
A smaller protein which will be non functional
Splice-site mutation is
Some introns being kept in the mature transcript or some exons being removed from the mature transcript
Chromosome structure mutations involve
The changing of a section of a chromosome
Substantial changes in chromosomes from mutations often
Make them lethal
Deletion is when
A section of a chromosome is removed
Inversion is when
A section of a chromosome is reversed
Translocation is when
A section of a chromosome is attached to another chromosome that is not its homologous partner
Duplication is when
A section of chromosome is added from its homologous partner
Homologous partner is
Matching chromosome
Duplication of a gene produces
A second copy that is free from selection pressures so the organism can mutate to produce new DNA sequences
