A dipeptide is formed when two amino acids (in this case leucine and alanine) combine together. The -CONH- bond between the
amino acid residues is called a
peptide bond.
If the condensation process is repeated with one more amino-acid it will make a tripeptide, or if many amino-acids are combined the result is a polypeptide.
In each of these cases, there is an unattached
amino group (-NH
2) at one end as well as an unattached
acid group (-COOH) at the other end of the chain of amino acid residues. These are called the N-terminus and the C-terminus.
Other options:
Label the peptide bond atoms.
Highlight leucine residue
Highlight alanine residue