What defines the quaternary structure of a protein?

Show Answers

The specific order of amino acids within a polypeptide chainThe interactions among amino acids within one polypeptide chainThe interactions between amino acids in two polypeptide chainsThe organization and interactions among multiple polypeptide chains in a protein composed of more than two chains

Explanation

Option A describes the primary structure, which is the amino acid sequence. Option B refers to the tertiary structure, involving interactions within a single polypeptide. Option C relates to interactions between two polypeptides but does not fully encompass quaternary structure. Option D correctly defines quaternary structure as the arrangement and interaction of multiple polypeptide chains in proteins with more than two subunits.