Cell wall and cell membrane sound similar but there are some critical differences which everyone studying them should know.
The cell membrane which is also known as the plasma membrane is a biological limiting membrane that separates the internal environment of all living cells from the external environment and thus, protects the cell. On the other hand, a cell wall is a structural layer present just outside the cell membrane. It can be found in bacterial, fungal, and plant cells.
This article will help you understand the main concepts and key differences between a cell wall and a cell membrane.
What is a Cell Membrane?
A cell membrane, also known as a plasma membrane, is a thin biological layer that surrounds every living cell. It plays an essential role in delimiting the interior cell environment from the exterior environment around it.
All the cellular constituents like cell organelles and other components are found within the cell membrane. The cell membrane is semi-permeable in nature and allows only particular solute molecules to pass through it.
What is a Cell Wall?
A cell wall is a special type of extracellular matrix that is the outermost layer in every plant cell. The cell wall is responsible for many characteristics that distinguish plant cells from animal cells.
Cell wall plays an important function in maintaining the structure and function of the cells they are found in. Some of these include
- Mechanical protection and a chemically buffered environment
- Providing a porous medium for the circulation and distribution of molecules
- Providing rigid building blocks to stabilize the structures.
- Providing a site of regulatory molecules that sense the presence of pathogens
Differences between the cell membrane and cell wall
Now that we have understood what exactly cell membrane and cell wall are, let’s look at this table on what is the difference between the cell wall and cell membrane:
|Cell membrane||Cell wall|
|The cell membrane is found in all living cells.||The cell wall is typically found only in bacterial, fungal, and plant cells.|
|It is semi-permeable in nature.||It is fully permeable in nature.|
|It plays an important role in the protection of the protoplasm.||It plays an important role in the protection of the protoplasm and provides mechanical rigidity to the cells.|
|It is made up of lipids, proteins, and carbohydrates.||It is made up of peptidoglycan in bacteria, chitin in fungi, and cellulose in plant cells.|
|It is a metabolically active structure, hence living.||It is a dead structure and is inactive.|
The cell membrane or plasma membrane is the outer covering of the living cell, which encloses the cytoplasm and the nucleus.
Forming the interface between adjacent cells, plant cell walls often play important roles in intercellular communication. Plant cell walls play an essential role in plant-microbe interactions, including defence responses against potential pathogens.