Question

The top on is the normal DNA and the corresponding mRNA sequence. The bottom is the DNA and mRNA sequence after a mutation. Answer the following questions:

NORMAL:

Template DNA 5' - CA TAC GTA TTG CAG ATT - 3'

mRNA 5' - __________________________________

MUTATED:

Template DNA 5' - CA AC GTA ATT GCA GAT T - 3'

mRNA 5' - _________________________________

(a) What is the amino acid sequence for the normal protein?

(b) What is the amino acid sequence for the mutated protein?

(c) What will be the effect of the mutation on the phenotype (large, small, or none)?

Answer 1

Answer.

Normal:

mRNA 5' GUA UGC AUA ACG UCU AA 3^'

Answer a. Primary polypeptide: N terimus-Val-Cys-Ile-Thr- Set-C terminus

AA sequence of base has been skipped because this sequence needs to have 1 more base, then only it will act as a codon and its amino acid will be coded.

MUTATED :

mRNA 5^' GUU GCA UUA ACG UCU AA 3^'

^{Answer b. Primary polypeptide: N terminus-Val-Ala-Leu-Thr-Ser-C terminus}

^{Answer c.} The effect will be large because the amino acid sequence has been changed from the normal to the mutated.