Gene mutation

Question 1

what is a mutation

Answer 1

random change to genetic material, either DNA or chromosomes, can change number of chromosomes
-occur during DNA replication before nuclear division

Question 2

what can cause mutations

Answer 2

natural= spontaneous, random mutation during DNA replication without outside influence

mutagens= radiation, viruses, mutagenic chemicals e.g in cigarettes and pesticide

Question 3

what are the three types of substitution/ point mutation

Answer 3

base is replaced by another
-silent
-missence
-nonsence

Question 4

what is a silent mutation and its effect on protein

Answer 4

-when a correct amino acid is still inserted despite a different base/mutation

-no effect, functional protein due to degenerate nature of the genetic code

Question 5

what is a missense mutation and its effect on a protein

Answer 5

wrong amino acid inserted due to replaced base

if amino acid is crucial for protein folding= different shape= none functional protein

Question 6

what is a nonsense mutation and its effect on a protein

Answer 6

stop codon inserted= truncated protein

shortened protein= non functional and may be broken down by the cell

Question 7

what is an insertion or deletion (indel) mutation

Answer 7

base or bases are indel which causes a frame shift

non-functional protein