Which plant feature are the small openings on the underside of leaves?

Which plant feature are the small openings on the underside of leaves?

• A. Lenticles
• B. Pneumatophores
• C. Stomata
• D. Nodes

Answer: (C)

Gas exchange in leaves occurs mainly through openings called stomata. These tiny pores are usually on the underside of the leaf and are surrounded by guard cells that control their size. When conditions are favorable, guard cells swell and the stomata open to allow carbon dioxide to enter for photosynthesis and water vapor plus oxygen to exit. When it's dry or hot, the guard cells lose water and the stomata close to conserve moisture. This arrangement on the leaf’s underside helps balance the need for gas exchange with minimizing water loss. Lenticels are openings on stems for gas exchange in woody tissue, not on leaf surfaces. Pneumatophores are specialized aerial roots used by some plants (like certain mangroves) to access air in flooded soils. Nodes are points along a stem where leaves or buds attach, not pores on the leaf surface.

Gas exchange in leaves occurs mainly through openings called stomata. These tiny pores are usually on the underside of the leaf and are surrounded by guard cells that control their size. When conditions are favorable, guard cells swell and the stomata open to allow carbon dioxide to enter for photosynthesis and water vapor plus oxygen to exit. When it's dry or hot, the guard cells lose water and the stomata close to conserve moisture. This arrangement on the leaf’s underside helps balance the need for gas exchange with minimizing water loss.

Lenticels are openings on stems for gas exchange in woody tissue, not on leaf surfaces. Pneumatophores are specialized aerial roots used by some plants (like certain mangroves) to access air in flooded soils. Nodes are points along a stem where leaves or buds attach, not pores on the leaf surface.