1. Leaf Notes

2. Leaf Diagram

3. Evolution of Photosynthesis First organisms = heterotrophic Problem: Too many organisms, not enough food Certain cells gained the ability to produce food using sun energy

4. Leaf Structure and Function Leaf = Photosynthesis “Machine”

5. Parts of a Leaf Epidermis = tightly packed cells, outermost covering Cuticle = waxy surface covering, prevents water loss

6. Parts of a Leaf Palisade Mesophyll= tightly packed cells, upper side of leaf, does majority of photosynthesis Spongy Mesophyll= loosely packed cells, lower side of leaf, lots of gas space, not as much photosynthesis

7. Parts of a Leaf Vascular Tissue = transport water and food for leaf –Xylem= transports water and dissolved minerals –Phloem= transports sugars and nutrients

8. Parts of a Leaf Stomata= openings in the epidermis. Allow for gas exchange (O 2 and water vapor out and CO 2 in) Guard Cells = control opening and closing of stomates.

9. Stomata Regulation Lots of water = guard cells swell and open stomates (photosynthesis happens). Little water= guard cells shrink and stomates close (no photosynthesis).