Explanation

Protein synthesis or translation consists of ribosomes, amino acids, mRNA, tRNAs and aminoacyl tRNA synthetases. The ribosomes have two binding sites namely aminoacyl site or A-site and peptide site or P-site. The starting amino acid methionine lies at the P-site of the ribosome. The next incoming tRNA is called amino acyl tRNA, it is bound to A-site. A peptide bond is formed between COOH group of the tRNA at P-site and NH₂ group of aminoacyl tRNA. This is facilitated by the enzyme peptidyl transferase and does not require high energy phosphate bonds.