Final answer:
A protein's secondary structure forms from hydrogen bonding between carbonyl and amino groups forming helices and sheets, known as α-helices and β-pleated sheets, which are crucial for the protein's stability and function.
Step-by-step explanation:
A protein's secondary structure contains helices and sheets that form from hydrogen bonding between carboxyl and amino groups of the different polypeptide chains. This hydrogen bonding occurs between the oxygen atom in a carbonyl group and the hydrogen atom of an amino group that is part of the peptide backbone. These bonds facilitate the folding of the polypeptide into either an α-helix or a β-pleated sheet.
The α-helix is stabilized by hydrogen bonds between the oxygen atom of the carbonyl group in one amino acid and the hydrogen atom in an amino group, which is typically four amino acids farther along the polypeptide chain. In contrast, the β-pleated sheet results from hydrogen bonds between segments of the polypeptide chain which may either fold back on themselves or pair with another polypeptide chain.
The formation of helices and sheets is crucial for the protein's overall structure and function, as it provides stability and contributes to the protein's unique three-dimensional configuration. These secondary structures can be separated by less structured areas known as random coils and can also contribute to the tertiary structure of the protein when the protein folds further.