1. Tissues, Chlorophyll, Canopy, Sun vs. Shade Leaves

2. Why are leaves green ?? Yes, the chlorophyll appear green… but why ??
Yes, the chlorophyll appear green… but why ??

3. Leaf Tissue Cuticle Water –repellent layer Releases Waxes
Limiting evaporation of water

4. Leaf Tissue Epidermis External layer One cell thick
Form an extra- thick cell wall

5. Leaf Tissue
Stomata
An open pore (stomatal pore) in the epidermis surrounded by guard cells
Found on the lower epidermis on the bottom of the leaf

6. Leaf Tissue Stomata Mechanism:
Guard cells open to let in CO2 and moisture for photosynthesis and release Oxygen
Guard cells are closed at night or when it is hot – no gas exchange , but it saves the plant from loosing water

8. Leaf Tissue Mesophyll Cells making up the internal leaf tissue
Palisade mesophyll
Spongy mesophyll

9. Leaf Tissue Palisade Mesophyll Upper layer of elongated cells
Contains chloroplasts
Specialized for gas exchange

10. Leaf Tissue Spongy Mesophyll Lower layer of irregular shaped cells
Contains large air spaces
Specialized for gas exchange

11. Leaf Tissue Vascular bundles
Visible veins of the leaf which connect through the petiole to the vascular tissue of the stem
Made up of Xylem and Phloem tubes, transporting water and food