Question

Sunken stomata can be traced in

• A. Nerium
• B. Musa
• C. Allium cepa
• D. All of the above

Answer 1

The correct option is D All of the above

Sunken stomata are found primarily in xerophytes. Rather than being on the leaf surface they are sunken into the leaf and usually are surrounded and partially covered by cuticle and hairs called as trichomes. Being from arid environments, photosynthesis uses and wastes a disproportionate amount of water, this variant, sunken rather than surface stomata, attempts to stem the water flow. The open sunken stomata are shielded from the drying winds. The hair-like trichomes maintain a moist atmosphere to slow down water loss. The gas exchanges can be accomplished with less water loss. With less water loss the stomata can remain open longer and thereby replenishing the CO${}_2$ levels inside the leaf and complete the photosynthetic processes for a greater part of the sunlit day than those plants that would have to close their stomata. Sunken stomata are present in all the options mentioned above.
Thus, the correct answer is option D.