Final answer:
Elongation is the second stage of protein synthesis where the ribosome moves along the mRNA, adding amino acids to the growing chain.
Step-by-step explanation:
Elongation is the second stage of protein synthesis, following initiation and preceding termination. During elongation, the ribosome moves along the mRNA molecule and adds amino acids to the growing polypeptide chain. This process involves the recognition of tRNA anticodons with mRNA codons, the attachment of amino acids to the polypeptide chain, and the movement of the ribosome along the mRNA to the next codon.