Final answer:
A peptide bond is a covalent bond between two amino acids, formed by dehydration synthesis when a carboxyl group of one amino acid joins with the amino group of the next, releasing water. Hydrolysis is the reverse process, breaking down peptide bonds by adding water.
Step-by-step explanation:
The peptide bond is a type of covalent bond that occurs between amino acids in proteins. This bond forms when the carboxyl group of one amino acid reacts with the amino group of another, in a dehydration synthesis or condensation reaction. During this process, a molecule of water is released, and it results in a peptide bond linking the two amino acids.
Conversely, a hydrolysis reaction is the process where a peptide bond is broken down. This happens with the addition of a water molecule, which effectively splits the amino acids apart. These two types of reactions are essential in the synthesis and degradation of proteins.