1. Mutations Flashcards
Mutation define
Any change to the based (nucleotide) sequence of DNA
Caused by errors during dna replication
Can be increased by mutagenic agents
Substitution
One or more bases swapped for another
Deletion
One or more based removed
Addition
One or more based added
Duplication
One or more bases reputed
Inversion
A sequence of bases is reversed
Translocation
Sequence of bases is moved from one location in the genome to another
Within same chromosome
Or
Movement to different chromosome
What does the order of dna bases in a gene determine ? How does mutation impact it ?
Sequence of amino acids in a particulate polypeptide.
If mutation occurs in gene, sequence of amino acids in the polypeptide that it codes for could be changed and it could change final 3D shape of protein.
Stops working
How can mutation affects enzyme ?
Change the shape of enzymes active site
This will stop substrates from being able to bind to the active site
Enzyme unable to catalyse reaction
What is the mutation of the gene BRCA1, what can it increase ?
Chance of developing breast cancer
What can some mutations cause ?
Cancer
Genetic disorder like cystic fibrosis
These are called hereditary mutations as mutation is present in new Fetus and passed onto off spring
What is cystic fibrosis ?
Genetic disorder of cell memebranes it results in body producing lots of thick sticky mucus in air passages and pancreas
How do not all mutations affect the order of amino acids in protein ?
Degenerate nature of genetic code means that some amino acids are ceded for by more than one dna triplets
So not all types of mutation result in change to akinos cud’s sequences of polypeptide
Which 2 mutations may not cause change in amino acid sequence ?
Inversion
Substitution
What 3 mutations cause a change in amino acid sequence ?
Addition
Duplications
Deletions
Change number of basses causing FRAME SHIFT so code is read differently
Impacts the downstream amino acids
