When amino acids are activated in the presence of ATP and linked to their cognate tRNA, the process is called:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Aminoacylation of tRNA
In the first phase of translation, each amino acid is activated by ATP and joined to its own tRNA. This step is called charging of tRNA, also called aminoacylation of tRNA. The charged tRNA then brings the amino acid to the ribosome.
(1) Aminoacylation of DNA — Incorrect. DNA does not carry amino acids. Only tRNA does.
(2) Aminoacylation of tRNA — Correct. It is the joining of an activated amino acid to its tRNA.
(3) Decharging of tRNA — Incorrect. This would mean removing the amino acid from the tRNA, which is the opposite of the step described.
(4) Charging of DNA — Incorrect. No such step exists. It is tRNA that is charged.
NCERT Extract:
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