Question : Assertion : A change in nitrogen bass atthe third position of a codon causeschange in the expression of the codon. Reason : A codon is mostly read by all the three nitrogen bases.

Question : Assertion : A change in nitrogen bass atthe third position

1.	Question : Assertion : A change in nitrogen bass atthe third position of a codon causeschange in the expression of the codon. Reason : A codon is mostly read by all the three nitrogen bases.
Answer» If both assertion and REASON are true and reason is the correct explanation of assertion If both assertion and reason are true butreason is notthe correct explanation of assertion If assertion is true but reason is false if both assertion and reason are false. Solution :(d) : According to the WOBBLE hypothesis , only the FIRST TWO position of a triplet codon on mRNAhave a PRECISE pairing with the bases of the tRNAanticodon . The pairing of thethirdposition bases of the codon may be ambiguous and varies according to the nucleotide present in this position. Thus ,a single tRNA type is able to recognise twoor more codonsdiffering only in the third base. The same is called wobble position.