Molecular Basis of Inheritance Question 77
77. What would happen if in a gene encoding a polypeptide of 50 amino acids, 25th codon (UAU) is mutated to UAA?
[2003]
(a) A polypeptide of 25 amino acids will be formed
(b) A polypeptide of 24 amino acids will be formed
(c) Two polypeptides of 24 and 25 amino acids will be formed
(d) A polypeptide of 49 amino acids will be formed
Show Answer
Answer : b
Hints & Solution
(b) UAA is the stop codon. Therefore at 25th amino acid the synthesis of polypeptide stops. So, a polypeptide of 24 amino acids is formed.