Chapter 11

Stomata opens because of (a) Oxygen in the air (b) Increased turgidity of the guard cells brought about by the cxposure to light (c) Vacuoles in guard cells (d) All the above

The transpiration is regulated by the movements of (a) Subsidiary cells of the leaves (b) Guard cells of the stomata (c) Mesophyll tissue cells (d) Epidermal cells of the leaves

Guttation is caused due to (a) Imbibitions (b) Osmosis (c) Positive root pressure (d) Transpiration

Guttation usually occurs when the plant is put in a (a) More saturated atmosphere (b) More humid soil (c) Dry condition (d) Desert

Guttation is the process of elimination of water from plants. It occurs from the pores in leaves through which water comes out in the form of droplets or a specialized multicellular structure in leaves which excretes water droplets. The pores are called (a) Stomata (b) Hydathodes (c) Lenticels (d) Wounds

Guttation is found mostly in (a) Herbaceous plants (b) Shrubs (c) Wood plants (d) None of these

Water lost by guttation is (a) Pure (b) Mixed with salts (c) Sometimes pure and sometimes impure (d) None of these

Guttation occurs in (a) Morning (b) Night (c) Evening (d) Morning 10 a.m.

Select from the following (in numbers) the correct function which are performed by transpiration. (1) Creates transpiration pull for absorption and transport of water in plant. (2) Transport minerals from the soil to all parts of the plant. (3) Cools the leaf surface (sometime \(10-15^{\circ} \mathrm{C}\) ). (4) Supplies water for photosynthesis. (5) Maintains the shape and structure of plants by keeping the cells turgid. (a) 1 (b) 3 (c) 4 (d) 5

\(\mathrm{C}_{4}\) plants are more evolved than \(\mathrm{C}_{3}\) plants because (a) \(\mathrm{C}_{4}\) plants are twice efficient in terms of carbon fixing. (b) \(\mathrm{C}_{4}\) plants loose only half of its water as \(\mathrm{C}_{3}\) plants for same amount of \(\mathrm{CO}_{2}\) fixed. (c) Both (a) and (b) (d) None of these