Plasmalemma

Plasmalemma (also known as the cell membrane or plasma membrane) is a biological membrane that separates the interior of all cells from the outside environment. The plasmalemma protects the cell from its surroundings and controls the movement of substances in and out of cells, providing quality control for the substances exported by the cell.

Structure

The plasmalemma is composed of a lipid bilayer, including phospholipids, which form a barrier to most water-soluble substances. Embedded within this lipid bilayer is a variety of protein molecules that act as channels and pumps, moving different molecules into and out of the cell.

Function

The primary function of the plasmalemma is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins. The plasmalemma controls the movement of substances in and out of cells and organelles. In this way, it is selectively permeable to ions and organic molecules.

Transport

The plasmalemma is involved in a variety of transport mechanisms, including passive transport, active transport, and vesicular transport. These transport mechanisms all require specific proteins in the membrane to function.

See also

• Cell biology
• Cell wall
• Endoplasmic reticulum
• Golgi apparatus
• Lysosome
• Mitochondrion
• Nucleus (cell)
• Organelle
• Peroxisome
• Ribosome