Question

why is plasma membrane called selectively permeable membrane ​

Answer 1

The plasma membrane is called a selectively permeable membrane as it permits the movement of only certain molecules in and out of the cells. It allows hydrophobic molecules and small polar molecules diffuse through the lipid layer, but does not allow ions and large polar molecules cannot diffuse through the membrane.

Answer 2

The cell membrane or plasma membrane is a biological membrane that separates the interior of the cell from the outside environment. The plasma membrane is called as selectively permeable membrane because it regulates the movement of substances in and out of the cell. It means that the plasma membrane allows some material to pass through it while at the same time it blocks other material from entering through it. 

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