Question

The meristem in which the cells divide in several planes is
A) Plate meristem
B) Rib meristem
C) Mass meristem
D) Lateral meristem

Answer 1

Hint: The meristem is the tissue in plants which comprises undifferentiated cells which have the capacity to divide and develop into any type of tissue or organs in plants. These cells after differentiation lose the capacity to divide. The different structures like leaf, root, stem etc are formed with respect to different planes of division.

Complete answer:
We are already aware of the meristematic tissues which are capable of dividing and forming any tissue or cell after differentiation. After attaining differentiation, they stop to divide. The meristematic activity is present in all the parts of the plants as the growth and differentiation of plants takes place at each and every part.

Let us discuss the plane of division and the types of meristems. The plane of division is important in determining the parts which are formed after the division. The several types of meristems are-
A) Plate meristem- In this the cell division takes place in two planes and consequently a plate of cells is formed. It takes place where the organs have flat configuration. Example: epidermis, leaf.
B) Rib meristem- In this the division takes place in one plane and a row of cells are formed. It gives rise to organs and tissues that have cylindrical form. For example, cortex.
C) Mass meristem- This kind of meristem is produced as a result of cell division in all planes. This results in producing mass of cells. The cells and tissues formed do not have a definite shape. For example, young embryo, endosperm and reproductive organs.
D) Lateral meristem- The result of this kind of division results in the increase in thickness. The cells divide in a radial direction. For example, vascular cambium.

Thus the correct answer is option ‘C’.

Note: Meristem is responsible for the growth of the plants. On the basis of the location of the division, the meristems are divided into:
- Apical meristem where the growth takes place at the tips.
- Intercalary meristem where the growth takes place at the middle.
- Lateral meristem where the growth takes place at the sides.