Which Level of Protein Structure Do the α Helix and the β

Question

Which level of protein structure do the α helix and the β pleated sheet represent?
A) primary
B) secondary
C) tertiary
D) quaternary
E) primary, secondary, tertiary, and quaternary

Accepted Answer

The α helix and the β pleated sheet represent the secondary level of protein structure, which refers to the local folding of polypeptide chains into regular structures such as helices and sheets. The primary structure is the linear sequence of amino acids, the tertiary structure refers to the overall three-dimensional shape of a polypeptide chain, and the quaternary structure involves the arrangement of multiple polypeptide chains into a functional protein complex.