Answer: The eukaryotic cell organelle that is tough and rigid, giving the cell its structure, is the cell wall. The cell wall is found in plant cells, fungal cells, and some protists.
The cell wall is composed of a tough, fibrous material called cellulose in plants and chitin in fungi. It provides structural support and protection to the cell, helping it maintain its shape and resist mechanical stress.
The cell wall also plays a role in cell-to-cell communication and prevents the cell from bursting when there is a high concentration of water inside the cell.
For example, in plants, the cell wall is responsible for the stiffness and rigidity of the plant's stems, leaves, and roots. It allows plants to stand upright and provides support for growth.
In summary, the cell wall is the eukaryotic cell organelle that is tough and rigid, giving the cell its structure. It is composed of cellulose in plants and chitin in fungi, and it provides support, protection, and communication for the cell.