The Difference Between Cell Wall and Cell Membrane
As the fundamental unit of life, the cell is a complex structure comprising several elements. Two of the most significant components of a cell are the cell wall and the cell membrane. While these terms are often used interchangeably, they refer to different structures that function differently. In this article, we will examine the difference between cell wall and cell membrane.
What is a Cell Wall?
A cell wall is a rigid layer that surrounds the plasma membrane of some cells, such as those found in plants, fungi, and bacteria. It is composed of cellulose, chitin, or other complex polysaccharides, and its primary function is to provide structural support and protection to the cell. The cell wall also helps regulate the movement of water and dissolved substances in and out of the cell.
What is a Cell Membrane?
A cell membrane, also known as a plasma membrane, is a thin layer that encases the cytoplasm of all cells. It is primarily composed of phospholipids, cholesterol, and proteins, and its primary function is to regulate the movement of substances in and out of the cell. The cell membrane also separates the internal environment of the cell from the external environment, helping to maintain the cell’s integrity and protecting it from harm.
The Differences Between Cell Wall and Cell Membrane
One of the most noticeable differences between cell wall and cell membrane is their structure. The cell wall is a thicker and more rigid structure that gives the cell its shape and helps it withstand external pressures. The cell membrane, on the other hand, is a thinner and more flexible structure that surrounds the cell’s cytoplasm.
Another significant difference between cell wall and cell membrane is their composition. The cell wall is primarily made up of complex polysaccharides, whereas the cell membrane contains phospholipids, cholesterol, and proteins. These differences in composition impact the functions of the two structures. The cell wall provides rigidity and support to the cell, while the cell membrane regulates the movement of substances in and out of the cell.
Finally, cell walls are only found in certain types of cells, such as those in plants, fungi, and bacteria. In contrast, cell membranes are present in all cells, including animal cells.
Conclusion
In summary, cell wall and cell membrane are two distinct structures that perform different functions in cells. The cell wall provides support, structure, and protection to the cell, while the cell membrane regulates the movement of substances in and out of the cell. Understanding the differences between these two structures is essential for comprehending the mechanisms of cells and the processes that occur within them.
Table difference between cell wall and cell membrane
| Cell Wall | Cell Membrane |
|---|---|
| Found in plant, fungi and bacterial cells | Found in all types of cells |
| Made up of cellulose (plants), chitin (fungi) or peptidoglycan (bacteria) | Made up of lipids and proteins |
| Rigid structure that provides support and protection to the cell | Flexible structure that controls the movement of materials in and out of the cell |
| Does not regulate the exchange of materials | Regulates the exchange of materials |
| Can survive in hypotonic conditions | May burst in hypotonic conditions |