In the b-pleated sheet conformation
A) there are hydrogen bonds perpendicular to the direction of the polypeptide chain.
B) the polypeptide chain is almost fully extended.
C) the polypeptide chains may be hydrogen bonded together in a parallel or antiparallel orientation.
D) all of these

Question

Quizplus · Accepted Answer

In the b-pleated sheet conformation:
A) There are hydrogen bonds perpendicular to the direction of the polypeptide chain. This is true because the hydrogen bonds are formed between adjacent strands that run parallel to each other but extend in opposite directions, resulting in a zigzag pattern.
B) The polypeptide chain is almost fully extended. This is partly true, but not completely. The strands are fully extended within each strand, but the overall shape of the sheet is often curved or twisted.
C) The polypeptide chains may be hydrogen bonded together in a parallel or antiparallel orientation. This is true because adjacent strands can run in the same direction (parallel) or opposite directions (antiparallel) and still form hydrogen bonds.

In the B-Pleated Sheet Conformation