Photosynthesis takes place largely in the the leaf (chloroplasts). Leaves are adapted to bring together the three raw materials of photosynthesis (water, co2 and light) and remove its products (oxygen and glucose) Adaptations: * A large S.A. that collects as much sunlight as possible * An arrangement of leaves on the plant that minimises overlapping and so avoids the shadowing of one leaf by another. * Thin, as most light is absorbed in the first few millimetres of the leaf, and the diffusion distance is this kept short. * A transparent cuticle and epidermis tha let ligh through to the photosynthetic mesophyll cells beneath. * Long, narrow upper mesophyll cells packed with chloroplasts that collect sunlight. * Numerous stomata for gaseous exchange . * Stomata that open and close in response to changes in light intensity. * Many air spaces in the lower mesophyll layer to allow diffusion of carbon dioxide and oxygen. * A network of xylem that brings water to the leaf cells, the phloem that carries away the sugars produced in photosynthesis.
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