2. 1 How do environmental factors affect the rate of photosynthesis? Light intensity The effect of light intensity on the rate of photosynthesis.

3. 1Set up the apparatus as shown. Keep the temperature constant. Turn on the lamp at a distance of 0.1m and allow the pond weed to equilibrate for 5 minutes. Investigation of the effect of light intensity on the rate of photosynthesis Procedure: bench lamp thermometer water rubber tubing clip pipette dilute sodium hydrogencarbonate solution Hydrilla

4. Investigation of the effect of light intensity on the rate of photosynthesis Procedure: bench lamp thermometer water rubber tubing clip pipette dilute sodium hydrogencarbonate solution Hydrilla 2Suck up the solution from the boiling tube. Close the clip completely and record the starting position of the meniscus in the pipette.

5. Investigation of the effect of light intensity on the rate of photosynthesis Procedure: bench lamp thermometer water rubber tubing clip pipette dilute sodium hydrogencarbonate solution Hydrilla 3After 5 minutes, record the final position of the meniscus in the pipette. Calculate the rate of photosynthesis. Record two more readings.

6. Investigation of the effect of light intensity on the rate of photosynthesis Procedure: bench lamp thermometer water rubber tubing clip pipette dilute sodium hydrogencarbonate solution Hydrilla 4Repeat steps 1 to 3 with the bench lamp placed at a distance of 0.2m, 03m, 0.4m and 0.5m from the apparatus.

7. 1 Light intensity 1) Initially, the rate of photosynthesis increases rapidly with increasing light intensity as more energy is supplied to the light reactions. rate of photosynthesis light intensity How do environmental factors affect the rate of photosynthesis?

8. 1 Light intensity 2) The increase stops when the light intensity reaches a saturation point. rate of photosynthesis light intensity saturation point ( 飽和點 ) How do environmental factors affect the rate of photosynthesis?

9. 1 Light intensity 3) The rate is now limited by others factors, e.g. CO 2 concentration and temperature. rate of photosynthesis light intensity saturation point ( 飽和點 ) rate limited by other factors How do environmental factors affect the rate of photosynthesis?

10. 2 CO 2 concentration The effect of carbon dioxide on the rate of photosynthesis.

11. 1) mid-rib branches into a network of veins two layers of tissues: palisade mesophyll & spongy mesophyll How do internal factors of plant affect the rate of photosynthesis?

12. 2) Palisade mesophyll  contain many chloroplasts  made up of tightly packed cylinder- shaped cells How do internal factors of plant affect the rate of photosynthesis?

13. 3) Spongy mesophyll  many air spaces  fewer chloroplasts  cells not regular in shape How do internal factors of plant affect the rate of photosynthesis?

14. 4) Epidermis  protects cells against mechanical injuries and infection  cover both surfaces How do internal factors of plant affect the rate of photosynthesis?

15. 4)  Epidermal cells have no chloroplasts, except guard cells How do internal factors of plant affect the rate of photosynthesis?

16. 5) Cuticle  reduces loss of water  cover the epidermis How do internal factors of plant affect the rate of photosynthesis?

17. 6) Stoma stoma guard cell  guard cells have many chloroplasts  surrounded by guard cells which control the opening and closing of the stoma How do internal factors of plant affect the rate of photosynthesis?

18. 6)  There are far fewer stomata on the upper surface of a leaf to reduce water loss. stoma guard cell How do internal factors of plant affect the rate of photosynthesis?

19. 7) Vascular bundles  contains xylem and phloem  for transport solutions containing chemical which plants need. How do internal factors of plant affect the rate of photosynthesis?

20. Xylem Phloem  transports water and minerals from the roots to the leaves  transports nutrients from the leaves How do internal factors of plant affect the rate of photosynthesis?