Which of the following statements about the plasma membrane is FALSE? A. The plasma membrane is described as a "fluid mosaic." B. The plasma membrane separates the cell from the extracellular fluid. C. The plasma membrane is a rigid, nonflexible structure. D. Phospholipids make up a large portion of the plasma membrane bilayer.

C. The plasma membrane is a rigid, nonflexible structure.

Explanation: a rigid plasma membrane will not allow passage of molecules across the cell membrane, osmosis and diffusion will not occur if the plasma membrane is rigid.

the plasma membrane or the cell membrane is not rigid but selectively permeable to ions and organic molecules such as sugar, CO2 and O2 and regulates the movement of substances across cells.

C

Explanation:

It is non rigid and flexible

Hope I am right

the denominator has a very specific role.