Wht is dedifferntation of cell and why does it occur n where does it occur

dear student.
dedifferentiation is process by which a already specialised cell (differentiated cell- which cannot divide) transforms back into an undifferentiated cell (stem cell) which has the ability to divide. dedifferentiation normally occurs in plant cells and in case of animals it is limited to lower animals such as worms, germ cells of drosophila etc.
Dedifferentiated cells are stem cells / pluripotent cells which can redifferentiate into any type of adult cell as per requirements.

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