Question

What is the difference between the cell wall and cell membrane?

Answer 1

Difference between Cell Wall and Cell Membrane

CELL WALL	CELL MEMBRANE
Present only in plants, and in some fungi, bacteria, algae.	Present in all types of cells, in human, animal, plant, bacterial, etc.
It is the outer non-living part of the cell but not an organelle which encloses cell membrane and provides a fixed shape.	It is an outermost, flexible, living organelle of the cell which provides shape to the cell.
It is made up of pectin, chitin, lignin, glycol proteins, glycolipids, sugar, and cellulose.	It is a lipid bilayer. And is composed of lipo proteins and carbohydrates.
The structure of the cell wall is 20- 80nm in thickness	The structure of the cell membrane is 7.5–10 nm in thickness
It is the thick and rigid structure with the fixed shape.	It is thin and delicate structure. It is flexible to change the shape as needed.
It protects the cell from the external environment.	It protects and maintains the internal environment of the cell.
The cell wall is elastic.	The cell membrane is non-elastic.
The cell wall is metabolically inactive	Cell membrane is metabolically active.
Cell wall lack receptors.	The cell membrane has receptors to receive signals from external chemicals.
The cell wall grows in thickness over time. Further, it occupies the whole cell in the plant as the cell ages and dies.	It is of the same thickness for the whole lifetime of the organism.
The cell wall is semi-permeable. It allows passage of substances with the size of 30-60 kD.	The membrane is permeable and controls the movement of the substance into and outside the cell. That is, it can allow water and other substance to pass through selectively.
Functions include protection from the external environment.	Functions include permeability, signal reception, motility conduction, cell division, sexual reproduction etc.