How are leaves of mesophytes suited to their function.(20mks)

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Broad / wide / flat lamina; to provide large S.A; for absorption of CO2/sunlight;

■Thin; to ensure short distance for CO2 to reach photosynthetic cells/palisade/mesophyll;

■Guard cells/ presence of stomata; for efficient diffusion of CO2 into leaf/ oxygen out of leaf/gaseous exchange/ water vapour/ transpiration.

■Transparent cuticle/epidermal cells; for penetration of light; into palisade cells/ photosynthetic
cells.

■Palisade cells contain many chloroplasts; to trap light (for photosynthesis);

■Chloroplasts have chlorophyll; for trapping light energy;

■Leaves have veins; Xylem to conduct water to photosynthetic cells; and phloem to translocate
the photosynthates to other parts of the plant;

■Air spaces in spongy mesophyll; for gases to circulate/diffuse easily/ for CO2 to diffuse into
palisade cells;

■Mosaic arrangement of leaves; enables all leaves to trap sunlight;

■Palisade cells are next to upper epidermis for maximum light absorption (by chloroplasts)

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