Question

Which of the following is incorrect?

• A. Cuticle is present on the epidermis of both stems and roots.
• B. The outer walls of guard cells are convex and thin.
• C. In grasses the guard cells are dumb bell shaped.
• D. The trichomes are usually multicellular.

Answer 1

Answer: (A)

A thick waxy layer called the cuticle which prevents the loss of water, covers the epidermis. Cuticle is present in stem but absent in roots. In grasses, the guard cells are dumb bell shaped. The outer walls of guard cells (away from the stomatal pore) are thin and the inner walls (towards the stomatal pore) are highly thickened. The guard cells possess chloroplasts and regulate the opening and closing of stomata. The epidermal hairs on stem are called trichomes. The trichomes in the shoot system are usually multicellular. They may be branched or unbranched and soft or stiff. They may even be secretory. The trichomes help in preventing water loss due to transpiration.