1. Photosynthesis

2. Overall equation

3. Structure of a Chloroplast

4. Chloroplasts have… DNA which is unique DNA in a loop Ribosomes similar to prokaryotes (70s) Reproduce by binary fision

5. Of course they have the pigment chlorophyll. This pigment is important because… It can convert light energy into electrical energy (an excited electron).

6. Absorption Spectrums of Plant Pigments

7. So chlorphyll absorbs primarily? Red and blue light

8. This explains why plants appear __ because they reflect __ light. green

9. Chlorophyll a and b structure

10. Photosynthesis has 2 sets of reactions Light Reactions (light dependent - occurs in the thylakoid) - light energy is used to make ATP - water is split (photolysis) to obtain H ions for glucose, oxygen is released as O 2. Calvin Cycle (light independent - occurs in the stroma) - CO 2 from the air is combined with organic molecules (carbon fixation) and reduced by the addition of H ions. ATP provides the energy for this process. G3P (glucose) is the ultimate product.

12. How can you measure rates of photosynthesis? Oxygen produced CO 2 consumed Increase in biomass of a plant

13. What is the effect of temperature on photosynthesis?

14. Why does the graph show a peak with a quick drop off? Enzymes needed for photosynthesis reach the optimum temperature at (b) Enzymes become denatured (c)

15. How does light intensity effect the rate of photosynthesis?

16. Rates of photosynthesis are ___ related to Light Intensity. directly

17. Why does the graph peak and level off? Chlorophyll reaches a maximum rate that it can transport electrons and replace those electrons from water.

18. How does increasing concentration of CO 2 affect rates of photosynthesis?

19. Rates of photosynthesis are ___ related to CO 2 concentration. directly

20. Why does the rate of photosynthesis level off? There is only so much RuBP (the molecule CO 2 combines with) in the stroma of the chloroplast, so CO 2 can only be “fixed” so fast.

21. The End for SL Glucose and other organic compounds produced! Oxygen gas released!

22. 8.2 Photosynthesis

23. Draw and label a chloroplast Thylakoid Grana Stroma

24. Light Dependent Reactions Chlorophyll absorbs light energy, which boosts an electron to a higher energy level (photoactivation) This electron powers the Electron Transport Chain and the Proton Pump, which pumps H ions into the thylakoid (chemiosmosis) Water is split to replace the electron chlorophyll lost (photolysis) - producing more H+ and releasing O 2. Diffusing H ions are used as an energy source to make ATP, as they diffuse through ATP synthase. NADP combines with the H ions and the electrons to produce NADPH (reduction of NADP+)

25. Light Dependent Reactions

26. Light Independent Reactions - Calvin Cycle

27. Steps of the Calvin Cycle Carbon dioxide from the air combines with RuBP (C 5 ) - (Rubisco biphosphate) This is called “carbon fixation”. This immediately splits forming PGA (C 3 ) - (phosphoglycerate) ATP provides energy and NADPH is used to reduce PGA to G3P - (Glyceraldehyde 3- phosphate) G3P is used to make glucose, starch, and all other organic compounds the plant needs.

28. Light Independent Reactions - Calvin Cycle

29. How does the structure of the chloroplast relate to its efficient function? Thylakoids provide for a large surface area for light absorption. Small space inside the thylakoid for accumulation of protons (H+) Stroma is fluid for the free movement enzymes and substrates of the Calvin Cycle - light independent reactions

30. What are the limiting factors on the rates of photosynthesis? Light intensity Concentration of CO 2 Temperature Water availability

31. Photosynthesis It produces the vast majority of organic molecules on the planet. It is the only source of O 2 on planet Earth. Thank a plant today! The end.