試題詳解

20. In the α helix the hydrogen bonds:
(A) are roughly parallel to the axis of the helix.
(B) are roughly perpendicular to the axis of the helix.
(C) occur mainly between electronegative atoms of the R groups.
(D) occur only between some of the amino acids of the helix.
(E) occur only near the amino and carboxyl termini of the helix.