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Explain how leaves of mesophytes are suited to their functions.

Answer Text:
- Have broad and flat lamina – to increase surface area to trap maximum sunlight and take up more #CO_2# for photosynthesis.
- Are thin to reduce the distance for diffusing gases i.e carbon dioxide and oxygen, and also for maximum penetration of light to photosynthetic cells.
- Have palisade cells which contain numerous chloroplasts, especially on upper epidermis for maximum sunlight absorption directly from the sun. Palisades are also closely packed together with long axis and located beneath the upperepidermis to receive maximum light.
- Have thin veins that contain vascular tissue i.e xylem and phloem. Xylem conduct water and mineral salts from the soil to the leaves/ photosynthetic tissue/cells while phloem translocate soluble products of photosynthesis from the leaves to growing regions.
- Have stomata which allow diffusion of gases i.e carbon dioxide and oxygen and also allow transpiration to take place.
- Have a guard cell that control opening and closing of the stomata hence regulates exchange of gases and water loss.
- Cuticle and epidermis are transparent to allow easier penetration of light to palisade cells.
- The spongy mesophyll contains cells that are loosely packed or have large air spaces to allow easier circulation of gases and diffusion of gases in
and out of palisade cells.
- Epidermis is thin i.e one cell thick to reduce the distance for diffusing gases and ensure penetration of light to photosynthetic cells.