Question

What is a bond between two amino acids called?

Answer 1

Peptide bond`("a covalent bond")`.

Explanation:

Each amino acid molecule consists of an amino group`(NH_2)` and carboxyl group`(COOH)` and variant side chain`(R)` attached to an alpha carbon`(C)`. When the two amino acid come along each other, the positively charged `alpha`-amino group of one amino acid reacts with the negatively charged carboxyl group of another amino acid releasing water molecule`(H_2O)`. This reaction is called condensation reaction and the linkage formed b/w two amino acids is called peptide linkage or peptide bond.

That's how amino acids join by means of peptides bond to form long polypeptide chains if proteins.

Hope it helps...