Final answer:
Amino acids are attached to tRNA by enzymes known as aminoacyl-tRNA synthetases, which are integral to the translation process where ribosomes synthesize proteins from mRNA templates.
Step-by-step explanation:
The process of translation involves various components including mRNA, ribosomes, tRNA, and enzymes. Among these, aminoacyl-tRNA synthetases are crucial enzymes that facilitate the addition of amino acids to tRNA. When a tRNA molecule is charged with an amino acid, it is ready to participate in translation by carrying the amino acid to the ribosome, aligning its anticodon with the complementary mRNA codon. During translation, the ribosome moves along the mRNA, and tRNAs bring specific amino acids in sequence.
As the ribosome reads the codons of the mRNA, it catalyzes the formation of peptide bonds between adjacent amino acids, elongating the growing polypeptide chain. This process continues until a stop codon is reached, signaling termination. So, in the context of the question, amino acids are attached to tRNA by enzymes called aminoacyl-tRNA synthetases (answer e).