«If we add the right amino acid, the protein moves away from the eisosome, probably because it takes on a different conformation in the substrate - bound state.» (sciencedaily.com)
A ribosome looks at the first codon in a messenger RNA strand, finds the right amino acid for that codon, holds it, then looks at the next codon, finds its correct amino acid, stitches it to the first amino acid, then finds the third codon, and so on. (science.howstuffworks.com)
To pick the right amino acids, a ribosome takes the nucleotides in sets of three to encode for the 20 amino acids. (science.howstuffworks.com)