Which term refers to the area of the root where cells begin to differentiate?

The term that refers to the area of the root where cells begin to differentiate is known as the zone of differentiation. This is a critical stage in root development, where cells that have been produced in the meristematic zone start to undergo specialization. During this process, the cells take on specific functions and contribute to the various structures of the root, such as the epidermis, cortex, and vascular tissues.

In the zone of differentiation, the cells mature and develop specific features that allow them to perform their roles effectively within the plant system, such as nutrient absorption and anchorage. This zone directly follows the zone of elongation, where cells grow in size, but it is the differentiation phase where the functional capabilities of these cells are established.

In contrast, the root cap serves primarily to protect the growing tip of the root as it pushes through the soil and is not involved in differentiation. The meristematic zone is where cell division occurs, leading to new cell formation, while the zone of elongation is concerned with growth rather than specialization. Thus, understanding the distinct roles of these zones highlights why the zone of differentiation is the appropriate choice for this question.