What is the codon for selenocysteine?
(A) UAG (B) UGA (C) UAA (D) GUA
(B) Ans: B. UGA(Ref Harper 30/e p18, 286)Selenocysteine:Commonly termed "21st amino acid".Present in biological proteins.Not coded directly in genetic code.Instead encoded by a UGA codon.UGA codon - Normally a stop codon.This mechanism called as|"translational recoding".