Which component is found only in plant cells and not in animal cells?

The cell wall is a unique component of plant cells that distinguishes them from animal cells. The primary function of the cell wall is to provide structural support and protection to the plant cell. Composed mainly of cellulose, it forms a rigid barrier that helps maintain the shape of the cell and prevents the cell from bursting under osmotic pressure, which is especially important for cells in a hypotonic environment.

In contrast, animal cells do not have a cell wall. Instead, they are surrounded by a flexible cell membrane, which allows for a more dynamic shape and the ability to interact with the surrounding environment in a different manner. Other components such as cytoplasm and nucleus are found in both plant and animal cells, making them common to both cell types. Thus, the presence of a cell wall is an identifying feature of plant cells.