Question

why is the plasma membrane called a selective permeable membrane

Answer 1

Because it allows only certain materials to pass through it.It means only needed materials are sent.

Answer 2

$\green \hookrightarrow$ Plasma membrane called a selectively permeable membrane because it regulates the movement of substances from within to outside of the cell. This means that the plasma membrane allows the entry of some substances while preventing the movement of some other substance.

Hope it helps!!

*Cheers*