Mutation and DNA repair

Question 1

pyrimidine (C,T) to another, or purine (A,G) to another

Answer 1

transition

Question 2

pyrimidine (C,T) to a purine (A,G) and vise versa

Answer 2

tranversion

Question 3

mutations that occur naturally as result of natural processes are called

Answer 3

spontaneous mutations

Question 4

mutations from enviromental elements called mutagents

Answer 4

induced mutations

Question 5

which class of mutations can or do change the amino acid sequence of proteins but never truncate them?

Answer 5

mis-sense mutations

Question 6

codon and amino acid alterations

Answer 6

mis-sense mutation - alters codon + amino acid e.g. GAC to GAG
non-sense mutation - changes codon to stop codon - TAC to TAA
silent mutation - alter codon but do not change amino acid coded CCT-CCC
frame shift mutation - involve addition or deletion of nucleotides / size of one codon

Question 7

a temporary change in the structure of a nitrogenous base is called

Answer 7

a tautomeric shift

Question 8

what is Ames Test used to determine?

Answer 8

the mutagenicity of chemical compounds

Question 9

which type of in DNA repair mechanism is most important TO HUMANS in regard to removing and replacing pyrimidine dimers induced by UV LIGHT

Answer 9

nucleotide excision repair

Question 10

one of the most frequent trinucleotide repeats involves expansion of which of the following ?

Answer 10

CAG - trinucleotide repeat that causes several human genetic diseases trinucleotide repeat expansion