Final answer:
Parallel and antiparallel beta sheets are two different conformations of the beta pleated sheet structure in proteins.
Step-by-step explanation:
Parallel vs Antiparallel Beta Sheets
Parallel and antiparallel beta sheets are two different conformations of the beta pleated sheet structure in proteins. In a parallel beta sheet, the polypeptide chains run in the same direction, with the N-terminus of one chain aligned with the N-terminus of the neighboring chain. In an antiparallel beta sheet, the polypeptide chains run in opposite directions, with the N-terminus of one chain aligned with the C-terminus of the neighboring chain.
An example to illustrate this could be: