Leaf Structure Flashcards
Describe how the structure of the other epidermis relates to its function.
The upper epidermis is a thin layer of flattened cells that do not contain chlorophyll so that they are relatively transparent. They protect against water loss and regulates gas exchange and produces the cuticle’s waxy substance.
Describe how the structure of the waxy cuticle relates to its function.
The waxy cuticle is a transparent waxy non-living layer. Its function is to protect the leaf and provide a waterproof layer to reduce water loss. It allows light through to Palisade cells for photosynthesis and is thicker on the upper surface of the leaf as there is more warmth from the sun.
Describe the structure and function of Palisade cells.
Palisade cells are tall vertically aligned cells, adapted to photosynthesis by being packed with chloroplasts. Their main function is photosynthesis.
Describe the structure and function of spongy cells.
Spongy cells are loosely packed cells with fewer chloroplasts and surrounded by airspaces. It is less organised than the palisade layer which allows more space for gas exchange/transpiration.
Describe the structure and function of phloem.
Phloem are living cells with perforated endplates joined end to end to produce continuous vessels. Their function is to transport organic molecules produced in photosynthesis such as glucose.
Describe the structure and function of xylem.
Xylem are lignified dead cells with no end walls joined to form continuous vessels. The tubes are used to transport water and mineral ions around the tree/plant.
Describe the structure and function of Stomata.
Stigmata are pours on the underside of leaves. They are holes which allow plans to control levels of carbon dioxide and water vapour moving in and out of the leaf.
Describe the structure and function of guard cells.
Guard cells are kidney shaped cells with chloroplasts on either side of the stomatal pore.
