Final answer:
The primary structure of a protein is the sequence of amino acids in its polypeptide chain. Secondary structure refers to the folding of the polypeptide chain into repeating patterns. Tertiary structure is the overall three-dimensional shape of the protein.
Step-by-step explanation:
A protein's primary structure is the sequence of amino acids in its polypeptide chain. The primary structure is the first level of protein structure. It is determined by the specific order of amino acids in the chain. The primary structure of a protein is essential because it determines how the protein will fold and ultimately its function.
The secondary structure is formed when the polypeptide chain folds into repeating patterns like alpha helices or beta pleated sheets. These structures are stabilized by hydrogen bonds between the amino acids. The tertiary structure refers to the overall three-dimensional shape of the protein, which is influenced by interactions between amino acid side chains. Lastly, some proteins have a quaternary structure, which is the arrangement of multiple polypeptide chains.