Question

What is difference between cell wall and cell membrane?

Answer 1

Cell wall:

1. The outermost layer of the plant cell the is cell wall.
2. The cell wall is present only in plants and in some fungi, bacteria, and algae. It is present outside the cell membrane and is tough, flexible, and sometimes rigid in its texture.

Cell membrane:

1. The outermost layer of the animal cell is cell membrane.
2. The cell membrane is also known as the plasma membrane.
3. It is a semi-permeable membrane composed of lipids and proteins.

Cell wall	Cell membrane
1. Present only in plants and in some fungi, bacteria, algae.	1. Present in all types of cells, in humans, animals, plants, bacteria, etc.
2.It is made up of pectin, chitin, lignin, glycoproteins, glycolipids, sugar, and cellulose.	2.It is a lipid bilayer. And is composed of lipoproteins and carbohydrates.
3.The cell wall is 0.1 μm to several μm in thickness.	3.The cell membrane is 7.5–10 nm in thickness.
4.It is the thick and rigid structure with a fixed shape.	4.It is a thin and delicate structure. It is flexible to change the shape as needed.
5.It protects the cell from the external environment.	5.It protects and maintains the internal environment of the cell.
6.The cell wall is metabolically inactive. Thus, it is non-living in nature.	6.The cell membrane is metabolically active. Thus, it is living in nature.
7.The cell wall grows in thickness over time. Further, it occupies the whole cell in the plant as the cell ages and dies.	7.It is of the same thickness for the lifetime of the organism.
8.The cell wall is fully permeable to smaller molecules with the size of 30-60 kDa.	8.The membrane is selectively permeable and controls the movement of the substance into and outside the cell.
9.Functions include protection from the external environment.	9.Functions include permeability, signal reception, motility conduction, cell division, sexual reproduction, etc.