Large proteins, like DNA polymerase and hemoglobin, are often composed of several polypeptides that are linked together. The level of protein structure describes how the polypeptides are joined to create a larger complex.

Primary

Explanation: The primary level of protein structure explains the sequence of amino acid linked together by peptide bonds to form polypeptide chains . A slight change in the amino acid sequence of Hemoglobin can alter hemoglobin function.

The primary level of protein structure is essential in the function of the protein any alteration in the amino acid sequence can disrupt the function of the protein.

answer; i believe the answer is (polygenic inheritance;

digestion

it excretes wastes