Which of the Following is Responsible for the Alpha-Helical Structure

Question

Which of the following is responsible for the alpha-helical structure of proteins?
A) hydrogen bonds
B) ionic interactions
C) polar covalent bonds
D) hydrophobic interactions
E) nonpolar covalent bonds

Accepted Answer

Hydrogen bonds between the carbonyl oxygen of one amino acid and the amide hydrogen of another amino acid (four residues away) in the polypeptide chain are responsible for the formation and stability of the alpha-helical structure in proteins.