It's very kind of you to describe the chemical process, though I think the text description and image in the problem were enough for me.
Let's suppose the amino acids HO-A-H, HO-B-H and HO-C-H came together (I hope I got the sides correct!) to form HO-A-B-C-H.
Are HO-A- and -C-H "residues"? One of them lost an -H and the other an HO-, so they are "what's left over after whatever was going to happen has finished happening."
The text says as "every amino acid in a protein are residues except the leftmost and the rightmost ones", so those end ones are not residues.
But the IUPAC definition says it can lose one, or the other, or both, which would include the end ones as part of the definition.
Comments
It's very kind of you to describe the chemical process, though I think the text description and image in the problem were enough for me.
Let's suppose the amino acids HO-A-H, HO-B-H and HO-C-H came together (I hope I got the sides correct!) to form HO-A-B-C-H.
Are HO-A- and -C-H "residues"? One of them lost an -H and the other an HO-, so they are "what's left over after whatever was going to happen has finished happening."
The text says as "every amino acid in a protein are residues except the leftmost and the rightmost ones", so those end ones are not residues.
But the IUPAC definition says it can lose one, or the other, or both, which would include the end ones as part of the definition.