Question

difference between cell wall and cell membrane

Answer 1

cell wall : Plants cannot move from one place to another so they are not able to protect themselves from harsh weather conditions and from their enemies. That is why an extra covering in the form of the cell wall is present in plant cells. Cell wall is the outermost layer present in plant cells .
cell membrane: Cell membrane or plasma membrane is present in plants as well as in animal cells. It is a thin , elastic , delicate living membrane made up of lipids and proteins that separate s the cell from its surroundings.

Answer 2

Answer:

CELL WALL

CELL MEMBRANE

Present only in plants, and in some fungi, bacteria, algae. Present in all types of cells, in humans, animals, plants, bacteria, 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 lipoproteins 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 a 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 The 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.