The primary component of the cell wall is cellulose in plants. Cellulose is a complex carbohydrate that provides structural support to the cell wall, making it rigid and allowing plants to maintain their shape. It consists of long chains of glucose molecules tightly packed together, which contributes to the overall strength and stability of plant cells. This characteristic is crucial for plants as it helps them resist external pressures, prevents excessive water loss, and supports their upright growth. In addition, cellulose is also a key component in the dietary fiber of human nutrition.