Answer :

1) They surround ALL cells
2) They are made up of all kinds of molecules
3) They control the cells activity
4) They are lipids
5) They all vary in size 

The cell membrane is defined as the protective layer, which separates the interior of the cell from the outside surrounding.

Fun Facts about Cell Membrane

  • The cell membrane is composed of the double layer of phospholipids with embedded proteins.

  • The protein in the lipid bilayer plays a crucial role in the movement of substances across the cells membrane.

  • The cell membrane is selectively permeable, such that it only allows certain molecules to pass through them.

  • The cell membrane also consists of carbohydrates, which helps in cell adhesion and communication.

  • The cell membrane is also known as the plasma membrane and is found in every living organism.

Thus, the cell membrane is a protective layer that is permeable to certain molecules and plays a vital role in cell metabolism.

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