The undifferentiated cells in plants are meristematic cells. Meristematic cells are chief totipotent cells present in plants that are capable of active cell division to form differentiated tissues and organs in plants. These cells continuously differentiated till they lose the ability to divide.
Meristems are found in gymnosperm, angiosperm (monocot and dicots). Meristematic tissues are present in three different parts of the plants. Apical meristems present at the tips, intercalary meristems present at the middle at nodes/internodes and lateral meristems present at the sides of the plants.