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Photosynthesis. Chapter 7. Producer. Harvest sun energy Autotroph Organisms that make their own organic matter Carbohydrates Lipids Proteins Nucleic acid Photosynthesis chloroplast. Who Uses Photosynthesis . Who Uses Photosynthesis . Some protozoa. Who Uses Photosynthesis.
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Photosynthesis Chapter 7
Producer • Harvest sun energy • Autotroph • Organisms that make their own organic matter • Carbohydrates • Lipids • Proteins • Nucleic acid • Photosynthesis • chloroplast
Who Uses Photosynthesis Some protozoa
Who Uses Photosynthesis Some Bacteria like cyanobacteria
Photosynthesis • Harvest of light energy from sun and convert to glucose • Uses co2 & water • Produces glucose & oxygen • Occurs in the chloroplast • Uses pigments (Chlorophyll a & b) • Metabolic pathway (Reduction Oxidation) • Light phase • Dark phase (calvin cycle)
Photosynthesic Structures • Green parts of plants (or animals) contain chloroplasts • Concentrated in leaves • ½ million/ Sq mm • Chlorophyll (a&b) • Green pigment • Stomata used to regulate gas availability
Stomata • Regulate Gas exchange= co2, o2, water vapor • Reduce water evaporation 6Co2 + 6H2O C6H12O6 +6O2
Chloroplast • Membrane bound organelle • Stroma- space • Granum of stacked thylakoids • Site of photosynthesis • Interconnected membrane sacs Granum Stroma
Light • Electromagnetic energy (radiation) • Aka visible light • Contains energy • Light interacts with matter • Reflected • visible • Transmitted • Visible • Absorbed • Pigments • Energy form changes
Why are Plants are green? • Absorb red, orange, blue, green • Reflect or transmit green
Photosynthetic pigments • Chlorophyll a • Blue-green • Absorbs Violet-blue & red light • Chlorophyll b • Yellow-green • Accessory pigment • Absorbs Violet-blue & red-orange light • Carotinoids • Yellow-orange • Absorb violet & blue-green • Broaden absorption • Photoprotection • communication
Photosynthesis • Light reactions • Require light • Convert solar energy to chemical energy • Dark reactions • Synthesis • Produces sugar
Light stage • Converts light energy into chemical energy • Chlorophyll absorbs light • Use light energy to split water • H is taken from H2O • Produce oxygen gas as waste • Energy harvesting stage • Cycles ADP to ATP • Cycles NADP+ to NADPH Energy Harvesting
Electron from water travels down the electron transport chain • Creates H+ gradient • Chemiosmosis
So Far we have ATP & NADPH But doesn’t photosynthesis make sugar?? Where’s the Sugar?
Dark Reactions • Aka calvin cycle • Light independent • No direct investment of light required • Series of reactions that assemble glucose • Use co2 & energy sources (nadph, atp) from light reactions
Cellular Respiration vs Photosynthesis • Cellular Respiration • H from sugar to o to make water • exergonic • Electron transport chain harvests E • Photosynthesis • H from h2o to co2= sugar • Endogonic • Uses light energy to drive • Electron transport chain harvests