1. PHOTOSYNTHESIS Sun Hwa Dong

2. Photosynthesis Produces organic substances Uses light Energy, Simple inorganic substances Light Energy to Chemical Energy

3. Absorption of Light Sunlight = White light, but made up of wavelengths like red, green, blue Pigments absorb lights Red, Blue > Green Green light cannot be reflected

5. Absorption of Energy Some used to produce ATP. Some split water molecules – Photolysis of Water This forms Oxygen and Hydrogen.

6. CO ₂ is absorbed to make organic substances. Carbon in a gas to carbon in solid compounds – Carbon Fixation This involves use of Hydrogen from photolysis and Energy from ATP.

7. Measuring Rates of Photosynthesis Production of O ₂ : Aquatic plants release bubbles of O ₂ Uptake of CO ₂ :If CO ₂ is absorbed from water, the pH of water rises Increases in biomass : the rate of increase in biomass means more photosynthesis.

8. Effect of Light Intensity

9. Effect of CO ₂ Concentration Low light intensity - shortage of ATP and hydrogen

10. Effect of Temperature CO ₂ fixation is catalyzed by enzymes.

11. Limiting Factors Each factors can limit the rate when below optimal level. Combination of factors – only one factor furthest from its optimum limits When 2 of the factors are equally close to optimum, increasing them rises the rate.

12. Action and Absorption Spectra Action Spectra: % use of wavelengths of light in photosynthesis Absorption Spectra: % use of the wavelengths of visible light that are absorbed

13. Photoactivation Chlorophyll & accessory pigments - Photosystem Chlorophyll molecules in photosystem absorb light energy and pass it to 2 special chlorophyll molecules in the reaction centre. Electron within the molecules become excited and photoactivated.

14. Photophosphorylation Photophosphorylation: the production of ATP, using E from light which is carried out by thylakoids Thylakoids: regular “stack” of membranes that contain Photosystem I & Ⅱ, ATP synthase, a chain of electron carriers

15. Chemiosmosis 1. Protons pass across membrane and release E which is used by ATP synthase to produce ATP. 2. The coupling of ATP synthesis to electron transport via a concentration gradient of protons → CHEMIOSMOSIS

16. Chloroplasts structure Chloroplast envelop Thylakoids Small fluid filled spaces inside Thylakoids Mostly have stacks of thylakoids called grana Colorless fluid around Thylakoids = stroma

17. Bibliography Course Companion p95-108 Study Guide p21, p75,p76-81 Pearson: p 74-78, p227-236 http://biotransitioneng.wordpress.com/2009/05/10/fossils-fuels-%E2%80%93-a-great-problem/ http://botit.botany.wisc.edu/images/130/Chlorophyta/Eremosphaera_Images/Chloroplasts_MC.html Pearson Education, Inc., publishing as Benjamin Cummings http://www.cbu.edu/~seisen/Photosynthesis.htm http://helpmyphysics.co.uk/wordpress/?m=200902 http://botit.botany.wisc.edu/images/130/Chlorophyta/Eremosphaera_Images/Chloroplasts_MC.html http://generalhorticulture.tamu.edu/lectsupl/physiol/physiol.html http://fhs-bio-wiki.pbworks.com/Factors-effecting-the-rate-of-photosynthesis http://reefbuilders.com/2010/08/23/chlorophyll-f-a-newly-discovered-photosynthetic-pigment-uses-infrared-light/ www.theoremeinnovation.com/revolution-en.html www.firstrays.com/plants_and_light.htm http://image.absoluteastronomy.com/images/encyclopediaimages/c/ch/chemiosmosis1.png www.cbs.dtu.dk/staff/dave/roanoke/bio101ch07.htm micro.magnet.fsu.edu/.../chloroplasts.html

18. Vocabulary Photosynthesis: The process used by plants and other organisms to produce all their own organic substances (food), using only light energy and simple inorganic substances. Photolysis of water: Splitting of water by energy absorbed by chlorophyll. Carbon Fixation: The conversion of carbon in a gas to carbon in solid compounds. Photosystem: protein complexes involved in photosynthesis Photoactivation: The initial stage of photosynthesis in chlorophyll Molecules where the presence of light Energy raises the energy. Chemiosmosis: The coupling of ATP synthesis to electron transport via a concentration gradient of protons Photophosphorylation: the production of ATP, using E from light which is carried out by thylakoids Thylakoids: regular “stack” of membranes with very small fluid-filled spaces inside that contain Photosystem I & Ⅱ, ATP synthase, a chain of electron carriers Grana: stacks of thylakoids Stroma: a colorless fluid around the thylakoids that contains many different enzymes