Plants Structure – Leaves stem roots Leaves Function of leaves Trap light energy for photosynthesis Producing sugar from photosynthesis Exchange of gases – oxygen and carbon dioxide Structure Wide Helps to catch more light energy Thin Help get carbon dioxide from bottom to top of leaf for photosynthesis Leaf structure Greener on top CO2 gets in here Leaf diagram – palisade layer Most chlorophyll CO2 Leaf cell palisade Position? Upper surface of leaf Features? Box shape Chloroplasts Function? Photosynthesis Gas exchange Leaves are designed to allow carbon dioxide to get to the main chlorophyll layer at the top of the leaf They have small holes called stomata on the under surface Each hole is open & closed by 2 guard cells Leaf diagram – stoma and guard cells Stoma position Stoma is a small hole Its size is controlled by 2 guard cells closed open Stoma function is for gas exchange in the leaf Guard cell oxygen Provided plant is photosynthesising Carbon dioxide Stomata open and close at different times of the day When it is light the plant needs CO2 for photosynthesis so the stoma open At night (darkness) they close Gas exchange Roots – function and structure Hold plant in position Absorb water and minerals from the soil Specialised cells to increase surface area for water intake Wheat seed Root hairs Fragile parts of cells that grow from the main root They massively increase the surface area for absorption Root hair cells (x150) Root ‘B’ has had the hairs damaged - This powerpoint was kindly donated to www.worldofteaching.com http://www.worldofteaching.com is home to over a thousand powerpoints submitted by teachers. This is a completely free site and requires no registration. Please visit and I hope it will help in your teaching.