A tripeptide contains three amino acids linked by two peptide
linkages Similarly when four, five or six amino acids are linked, the respective
products are known as tetrapeptide, pentapeptide or hexapeptide,
respectively When the number of such amino acids is more than ten, then
the products are called polypeptides A polypeptide with more than hundred
amino acid residues, having molecular mass higher than 10,000u is called
a protein