Difference between cell wall and cell membrane

Cell wall

Cell wall is the outermost layer of cell.It is made up of mainly by cellulose other components may also forms cell wall in addition with cellulose in different organisms.It is a non-living structure.It provides shape to the cell and gives rigidity to form the outer covering.It has many functions.It protects the cell and its constituents against mechanical injuries such as damage and infection.Protects the cell from disease causing agents.It allows the substances to enter and leave the cell.It helps in the interaction of one cell to another cell mainly by calcium pectate which is middle lamella.cell wall is a characteristic feature in plants.It is also present in prokaryotes like monerans and also present in some eukaryotes except Animalia.Cell wall is absent in Animals.

Cell membrane


It is the layer next to the cell wall.Also called as plasma membrane.It is a living structure and very thin,delicate and flexible.Its function is to allow certain substances(not all substances) inside the cell so it is also called as Selectively permeable.cell membrane is composed of lipids.The most important function is to transport the molecules across it.The molecules can pass through the membrane by passive transport that is without any requirement of energy,Active transport that is with the utilisation of ATP.Cell membrane is present in all living organisms.

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