Question

tRNA has the function of

• A. Transcription
• B. Carrier for attaching amino acids over mRNA template
• C. Transferring information to mRNA
• D. Carrying genetic code to cytoplasm

Answer 1

Answer: (B)

Carrier for attaching amino acids over mRNA template

Transcription is the process of synthesis of RNA using DNA template; it is carried out in the nucleus by RNA polymerase that adds ribonucleotides to free 3’ hydroxyl group of primer which makes option A incorrect. The genetic information present in DNA is transferred to mRNA by transcription which makes option C incorrect. Messenger RNAs (mRNAs) specify the amino acid sequence of one or more polypeptides; a set of three nucleotides forms a codon which in turn specifies a particular amino acid. Thus it transfers genetic information from DNA to ribosomes in the cytoplasm which makes option D incorrect. Transfer RNAs (tRNAs) read the genetic information present in the form of triplets in the mRNA and transfer the appropriate amino acid to a growing polypeptide chain during protein synthesis. All tRNAs have about 73 to 93 nucleotide that folds into four base-paired stems and three loops. The anticodon loop has triplet at the tip which base pairs with the corresponding codon in mRNA and transfer the amino acid present at its 3' amino acid binding site thereby serving as an adaptor molecule. The correct answer is C.