What type of bond connects amino acids in a protein's primary structure?

In the primary structure of a protein, amino acids are linked together by peptide bonds. A peptide bond is a specific type of covalent bond formed when the carboxyl group of one amino acid reacts with the amino group of another, resulting in the release of a molecule of water (a condensation reaction). This bond is essential because it creates the backbone of the protein chain, allowing the sequence of amino acids to dictate the protein's specific properties and function.

This primary structure is crucial as it ultimately determines how the protein will fold into its secondary and tertiary structures, influencing its overall physiological roles. The formation of peptide bonds is a fundamental step in protein synthesis, leading to the creation of polypeptides that fold into functional proteins in biological systems.