Question

2 charecteristics of cell membrane

Answer 1

It acts as body guard for cell.....or it protect cell from outer atmosphere......
 separating the intracellular components from the extracellular environment.
2
The cell membrane protects the cell from some harmful chemicals in its external environmemt. 
It also protects the cell from loss of useful biological macromolecules held within the cell by its plasma membrane.

Answer 2

2 charecteristics of cell membrane are1.it gives definite shape to the cell.
2.it is semi permeable in nature and allows only some substances to pass through in and out of the cell therfore protecting it from harmful substances