Which of the following statement about the arrangement of a protein in three dimensions is false ?

Options

A. As a result of hydrogen bonding a portion of a protain may exist as a right - handed `alpha` - helix with 3.6 amino acid residues per turn, and a repeat unit of `5.4 Å`
B. As a result of hydrogen bonding a portion of a protein may exist as a pleated sheet, in which the repeat unit is `7.0 Å`
C. In a pleated sheet, the polyamide chains may be parallel or antiparallel
D. A portion of a protein may exist as a flat sheet with a repeat unit of `7.2 Å`

Answer

D

Explanation

In three dimensional structure protein does not exist as flat sheets.