Answer:
The root cells undergo mitosis to form new identical cells.
Step-by-step explanation:
Mitosis is the process of cell division, where a cell divides into two equal cells with the same number of chromosomes. These new cells are used to promote the growth of a biological structure, promoting an elongation, a replacement, a concert, or an increase in volume. This can be seen in the case of the growth of the tip of the onion root, where the cells underwent mitosis, forming equal cells, to promote the growth of a new tip.