why is the root tip a good area to study cells undergoing mitosis?

Answer 1

The root tip contains one of the plant's meristematic regions. These are places where there is frequent mitotic activity. Usually onion root tips are used because they are particularly large, and the mitotic rate is high.

Remember that plant tissues capable of mitosis are termed meristematic tissues, found as lateral meristem by which the stem widens and apical meristem, by which the stems lengthen. The root in plants is constantly growing both in width and height, which makes it easier to find cells undergoing mitosis.