Leaf Structure and Adaptations

photosynthesis

manufacture of food in the leaf

leaf structure adaptations for gaseous exchange

• air spaces

• stoma 

• mesophyll cells

• leaf shape

• stomal distribution

leaf - air space - adaptations for gaseous exchange

increases the surface area inside the leaf to maximise gaseous exchange across the surface of the spongy mesophyll cells  

leaf - stoma - adaptations for gaseous exchange

breathing pore - allows exchange of CO2 and O2 

leaf - mesophyll cells - adaptations for gaseous exchange

large surface area and moist surfaces to speed up gaseous exchange 

leaf - leaf shape - adaptations for gaseous exchange

leaves are thin and have a large surface area to increase diffusion of gases

leaf - stomal distribution - adaptations for gaseous exchange

spread out over leaves so waste gases can diffuse away quickly and not build up in the leaf 

leaf structure adaptations for photosynthesis

• waxy cuticle
• upper epidermis
• palisade mesophyll
• spongy mesophyll
• lower epidermis
• xylem
• phloem

leaf - waxy cuticle - adaptations for photosynthesis

waterproof to prevent water loss but allows light through 

leaf - upper epidermis - adaptations for photosynthesis

transparent to allow light through for photosynthesis
protective layer preventing the entry of pathogens 

leaf - palisade mesophyll - adaptations for photosynthesis

tall, thin cells - sausage shaped - packed closely together with many chloroplasts for the maximum absorption of light 

leaf - spongy mesophyll - adaptations for photosynthesis

large air spaces allow gases to circulate in the leaf
CO2 is needed by cells to photosynthesise

leaf - lower epidermis - adaptations for photosynthesis

has pores called stomata to allow CO2 in
guard cells can close stomata to reduce water loss

leaf - xylem - adaptations for photosynthesis

brings water to the leaf which is needed for photosynthesis

leaf - phloem - adaptations for photosynthesis

takes away the products of photosynthesis to other plant parts or for storage, e.g: starch