Question

Comment on the statement. 'Plasma membrane is made up of two components

Answer 1

Hint: Plasma membrane also called as the cell membrane is the membrane found in all cells that separates the inner part of the cell from its exterior. A cell wall is attached to the plasma membrane to its exterior in plants as well as bacterial cells. Plasma membrane is made up of a lipid layer that is semipermeable and is responsible to regulate the transportation of materials and also the movement of substances both in and out of the cell.


Complete answer:
Plasma membrane is the outer covering of the cell that is composed of phospholipid bilayer and proteins. The fundamental structure of the membrane is the phospholipid bilayer that forms a stable barrier between the two aqueous compartments. The lipids present in the plasma membrane consist of phospholipid , glycolipids and cholesterol which helps in maintaining the fluidity.

Plasma membrane is composed of the following constituents:
- Phospholipids that forms the ultimate fabric of the membrane
- Peripheral proteins which is present on the outer or inner surface of phospholipid bilayer but are not implanted in the hydrophobic core
- Cholesterol that is folded between the hydrophobic tails of phospholipid membrane
- Carbohydrates which is found to be attached to the lipids or proteins on the extracellular side of the membrane, leading to the formation of glycolipids and glycoproteins
- Integral proteins that is found to be implanted in the phospholipid bilayer

Note: It is impermeable to ions and water soluble molecules that cross membranes only through carriers, transmembrane channels and pumps. The transmembrane proteins nourishes the cell with nutrients, regulates the internal ion concentration and can also set up a transmembrane electrical potential.