Question

What will happen that plasma membrane is not present in cell?

Answer 1

Plasma membrane is selectively permeable. As a matter of fact it allows only some necessary things to pass through.  If a cell lacks plasma membrane toxins may enter and either put the cell to death or mutate it

Answer 2

What will happen that plasma membrane is not present in cell?

1. Cell not be able to exchange material from its surrounding.
2. Cells will die quickly on removal of cell membrane.