In tissue culture experiments, leaf mesophyll cells are put in a culture medium to form callus. This phenomenon may be called as:

Step-by-step solution

After the divisions are over, differentiation of a cell leads to the attribution of a specialised function. For example the cell forms mesophyll cells. When mesophyll cells are cultured, they form callus, which is an undifferentiated mass of cells. Thus, this is a process of dedifferentiation. The cell of callus can re-differentiate to form organs, or any tissue.