Question

In a longitudinal section of a root, starting from the tip to upward, the four zones occur in which of the following order?

• A. Root cap, cell division, cell maturation, cell enlargement
• B. Cell division, cell enlargement, cell maturation, root cap
• C. Cell division, cell maturation cell enlargement, root cap
• D. Root cap, cell division, cell enlargement, cell maturation

Answer 1

Answer: (D)

A typical root has four regions.

Root cap is parenchymatous, cap-like multicellular structure, that covers the root apical meristem. It secretes mucilage to lubricate the path of root in soil.

Root cap is followed by 1 mm long zone of growth, i.e., meristematic zone or cell division zone. Meristematic zone is characterized by compactly arranged thin walled cells with dense cytoplasm that produce new cells.

It is followed by 4-8mm long zone of elongation wherein the growing cells elongate and lose the power of division.

Last is zone of maturation, which forms major part of root; it has thick walled cells that are not involved in water absorption but in anchorage.