Below is a microscopic cross-section of a typical leaf (taken from a dicotyledonous plant)
- Distribution of tissues may differ between different types of plants according to functional requirements
Key Features:
- Palisade mesophyll is the site of photosynthesis and hence is located on the upper surface of the leaf (facing sunlight)
- Spongy mesophyll is the main site of gas exchange and is hence located on the lower surface of the leaf (near stomata)
- Stomata are on the underside of the leaf (prevents obstruction so as to maintain an open channel for gas exchange)
- The top surface of the leaf is covered by a thick, waxy cuticle (prevents water absorption which would affect transpiration)
- Vascular bundles (including xylem and phloem) are located centrally to allow for optimal access by all leaf cells