Concepts of biological peptides and peptide chains in senior high school.

Some amino acids make up protein, which may be condensed into one peptide chain or several peptide chains interwoven to form protein. A peptide chain composed of several amino acids is several peptides. Your first question is "1 peptide", which means that there is a 1 peptide chain, and five amino acids are pentapeptides, regardless of the number of amino acids. Let's take five amino acids as an example. I can synthesize two peptide chains, one with two amino acids, namely dipeptide, and the other with three amino acids, namely tripeptide. Peptide chain has nothing to do with peptide bond. The number of peptide bonds is equal to several peptides minus one. For example, there are two peptide bonds in the peptide chain of three peptides, which is the number of dehydration. Protein is not the focus of the college entrance examination. As long as we know the simple quantitative relationship, such as dehydration number = peptide bond number = peptide number minus 1.