Answer:
The α‑helix is held together by hydrogen bonds between the amide N−H and C=O groups.
Disulfide bonds stabilize secondary structure.
Step-by-step explanation:
Proteins have primary, secondary, tertiary and quartinary structures.
The secondary structure of a protein is the regular, recurring sequence of amino acid in a polypeptide chain. Secondary structure of proteins give rise to the folding observed in the structure of a protein.
The major secondary structures of a protein are α-helices and β-structures.