why is it important that the cell membrane is semipermeable
All cells are enclosed with a cell membrane. A selectively permeable cell membrane is one that allows certain molecules or ions to pass through it by means of active or passive transport.Active transport processes require the cell to expend energy to move the materials, while passive transport can be done without using cellular energy.he most common example is the phospholipid bilayer cell membrane that surrounds every cell in our bodies. Another example of a selectively permeable membrane is the inner membranes of an egg. All cells in our body are surrounded by a phospholipid bilayer.