1. CO 7 Chapter 8 Photosynthesis

2. What is a plant anyway? Name 3 plants you have seen recently. Photosynthetic Organisms A. Photosynthesis transforms solar energy B. Organic molecules built by photosynthesis provide both the building blocks and energy for cells.

3. Figure 7.1b C. Plants use the raw materials: carbon dioxide and water D. Chloroplasts carry out photosynthesis

4. Figure 7.1c E. Chlorophylls and other pigments involved in absorption of solar energy reside within thylakoid membranes of chloroplasts

5. Figure 7.2

6. Plants are Solar Energy Converters A. Solar Radiation - Only 55% of solar radiation that hits the earth’s atmosphere reaches surface; most is visible light.

7. B. Photosynthetic Pigments - Pigments found in chlorophyll absorb various portions of visible light; absorption spectrum. 1. Two major photosynthetic pigments are chlorophyll a and chlorophyll b. 2. Both chlorophylls absorb violet, blue, and red wavelengths best. 3. Most green is reflected back; this is why leaves appear green.

8. 4. Carotenoids are yellow-orange pigments which absorb light in violet, blue, and green regions. 5. When chlorophyll breaks down in fall, the yellow-orange pigments in leaves show through.

10. Photosynthetic Reaction 1. In 1930 C. B. Van Niel showed that O 2 given off by photosynthesis comes from water and not from CO 2. 2. The net equation reads:

11. E. Two Sets of Reactions in Photosynthesis 1. Light reactions cannot take place unless light is present. They are the energy-capturing reactions.

13. b. Chlorophyl within thylakoid membranes absorbs solar energy and energizes electrons. c. Energized electrons move down the electron transport system; energy is captures and used for ATP production. d. Energized electrons are also taken up by NADP+, becoming NADPH.

14. 2. Calvin Cycle Reactions a.These reactions take place in the stroma; can occur in either the light or the dark. b. These are synthesis reactions that use NADPH and ATP to reduce CO2. -- and make a carbohydrate, sugar

15. The Calvin Cycle Also called *The Light Independent Reactions *The Dark Reactions *Named after Melvin Calvin, who used a radioactive isotope of carbon to trace the reactions.

16. What you should know by now.. 1. The equation for photosynthesis. Write it! 2. The structure of a chloroplast. Sketch it! 3. Compare Absorption Spectrum to Action Spectrum. Color it! 4. Compare the two stages of photosynthesis and their products. Chart it! **Things are about to get much more difficult**

17. Are you still confused? This is pretty hard to visualize, but through the magic of technology, we can watch these processes as animations McGraw Hill Animation Forest Biology - The Light Reactions

18. Quick Practice

19. thylakoid O2O2 stroma grana