Question

Which of the following character is not applicable to tRNA?

• A. It is the smallest of the RNAs.
• B. It acts as an adapter for amino acids.
• C. It has a clover leaf like structure.
• D. It bears NODOC.
• E. It is the largest of the RNAs.

Answer 1

Answer: (E)

It is the largest of the RNAs.

All tRNAs have about 73 to 93 nucleotides that fold into four base-paired stems and three loops; it is smallest RNA, mRNA being the largest one. Option A is correct but E is incorrect. Four base-paired stems and three loops (D- loop, T psi C loop and anticodon loop) gives it a clover leaf structure; option C is correct. The 3' end has CCA sequence. Attachment of an amino acid to the 3 adenosine yields an aminoacyl-tRNA; option B is correct. The anticodon loop has triplet at the tip which base pairs with the corresponding codon in mRNA. Since, the first base of anticodon pairs with third base of mRNA codons; the anticodon is also termed as NODOC, the opposite of CODON.