The Importance of Cell Walls in Plant and Animal Cells

Cell walls are an essential attribute of plant cells. However, did you know that animal cells, in some instances, also have cell walls? In this article, we will explore the significance of the cell walls in plant and animal cells, the composition of the cell wall, and the differences between the two.

What is a Cell Wall?

A cell wall is a rigid, protective layer that covers the cell membrane of plant cells. It is located outside the cell membrane and surrounds the cell, giving it shape and support. In contrast, animal cells lack an outer membrane or cell wall. Instead, they have a flexible plasma membrane that encases the cell.

Composition of the Cell Wall

The cell wall of a plant is composed of cellulose, hemicellulose, and lignin. Cellulose is a polysaccharide, a complex carbohydrate that is insoluble in water, while hemicellulose is a short-chain polysaccharide. The mixture of the two creates a rigid, sturdy structure that gives the plant its shape.

On the other hand, animal cells, when present with cell walls, have a different composition. Chitin is the primary component of cell walls in certain organisms, such as insects and crustaceans. In contrast, animal fossils are made up of a polymer known as peptidoglycan.

Importance of Cell Walls in Plants

As previously stated, cell walls provide a plant with structural support, allowing it to stay upright despite gravity. Cell walls also prevent the plant from drying out and act as a barrier against parasites and other cellular invaders.

Moreover, the cell wall is responsible for controlling water intake in plants. When a plant is exposed to a high concentration of salt, the plant's cell wall absorbs the salt ions and prevents excess water from entering the plant.

Importance of Cell Walls in Animals

While animals do not require a cell wall to provide a structure, in some species, the cell wall is an essential attribute. For instance, sponges are animals, and they have a fibrous cell wall composed of collagen that provides structure and support.

Moreover, some animal species use a cell wall as a means of defending themselves. The cell wall is responsible for creating barriers and preventing parasites or foreign substances from entering the cell.

The Differences Between the Cell Walls in Plants and Animals

Aside from their compositional differences, there are other distinctions between the cell walls of plant and animal cells.

One significant difference is the surrounding tissue. In plants, the cell wall is surrounded by a flexible material referred to as the middle lamella, which helps anchor one cell to the next. In contrast, animal cells lack middle lamella.

Additionally, the way in which the cell walls are created differs. Plants generate cell walls by synthesizing new components and depositing them on the outside membrane. In contrast, the formation of the cell wall in animals occurs primarily during the cell division process.

Conclusion

Cell walls are vital attributes of plant and animal cells, affecting a wide range of functions, particularly those associated with structure, protection, and water intake. While there are significant differences between the cell walls of both types of cells, they play essential roles in the growth and survival of the organism.