Interfascicular cambium develop from cells of
A) Pericycle
B) Medullary rays
C) Xylem parenchyma
D) Endodermis

Hint: Cambium is the layer of dividing tissue. The cambium which occupies space in between two vascular bundles is called interfascicular cambium. It consists of actively dividing cells which form xylem and phloem.

Complete Answer:
- A cambia in plants is a layer of tissue that provides partially differentiated cells for the growth. It is found in between xylem and phloem.
- Interfascicular cambium is actively dividing cells which produce xylem towards the inner side and phloem towards the outer side. It is a secondary meristem and hence increases the girth of the plant.
- Interfascicular cells are derived from the permanent tissue. It originates from the parenchymatous cells after differentiation of the fascicular cambium. Medullary rays are the parenchymatous cells which give rise to interfascicular cambium.
- Pericycle- It is a non-vascular tissue in plants. It encircles the vascular tissue.
- Xylem parenchyma- These are the only living cells in the xylem. They are formed from interfascicular cambium.
- Endodermis- It is the thin layer of cells in the cortex (adjacent to the pericycle) of roots and stem surrounding the vascular bundles.

Thus the correct answer is B. Interfascicular cambium develops from the cells of medullary rays.

Additional Information: In dicot stem, the fascicular and interfascicular cambium together form a ring of meristematic tissue called the vascular cambium. It happens during the secondary growth.

Note: Interfascicular cambium is present in between primary xylem and phloem. It is derived from embryonic meristem . It is present in the primary meristem but active during the secondary growth of the plant