Question

The amino acid attaches to the tRNA at its ______.

Options

• 3’-end

• 5’-end

• anti-codon site

• none of these.

Answer 1

The amino acid attaches to the tRNA at its 3’-end.

Explanation:

In a tRNA molecule, the amino acid attaches to a specific site known as the acceptor stem, which is located at the 3’-end of the strand. This end always terminates with a universal three-base sequence: CCA. An enzyme called aminoacyl-tRNA synthetase facilitates a chemical bond between the carboxyl group of a specific amino acid and the hydroxyl group of the ribose sugar at the 3’ terminal. While the anticodon at the opposite end of the tRNA identifies the correct spot on the mRNA, it is the 3’-end that physically carries the amino acid building block to the ribosome.