How do cell walls in plant cells differ from animal cells?

Plant cells have a rigid cell wall for structure and support, while animal cells do not have a cell wall.

In more detail, the primary difference between plant and animal cells lies in the presence of a cell wall in plant cells. This cell wall is a rigid layer that surrounds the cell membrane, providing the cell with structural support and protection. It is primarily composed of cellulose, a complex carbohydrate, along with other components like hemicellulose, pectin, and proteins. This rigid structure allows the plant to maintain its shape and resist the external pressures of its environment, such as wind or water pressure.

On the other hand, animal cells do not possess a cell wall. Instead, they have a flexible cell membrane made up of a phospholipid bilayer. This flexibility allows animal cells to change shape and move, which is crucial for many biological processes such as cell division, growth, and the ability to interact with other cells.

The absence of a cell wall in animal cells also means they are more susceptible to changes in their environment. For example, if an animal cell is placed in a hypotonic solution (a solution with a lower solute concentration than the cell), water will rush into the cell due to osmosis, potentially causing the cell to burst. In contrast, the rigid cell wall of a plant cell can prevent this from happening, providing an extra layer of protection.

In summary, the presence of a cell wall in plant cells provides them with structural support and protection, while the absence of a cell wall in animal cells allows for greater flexibility and interaction with their environment. This fundamental difference is a key factor in the diverse functions and behaviours of plant and animal cells.