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Photosynthesis. Converting Solar Power to Chemical Energy. General Equation. CO 2 + H 2 O + Sunlight C 6 H 12 O 6 + O 2. Translation: Photosynthesis uses light energy to convert carbon dioxide into glucose that can be used by organisms. LIGHT ENERGY. 12H 2 O + 6CO 2.
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Photosynthesis Converting Solar Power to Chemical Energy
General Equation CO2 + H2O + Sunlight C6H12O6 + O2 Translation: Photosynthesis uses light energy to convert carbon dioxide into glucose that can be used by organisms.
LIGHT ENERGY 12H2O + 6CO2 6O2 + C2H12O6 + 6H2O WATER CARBON DIOXIDE OXYGEN GLUCOSE WATER in-text, p. 93
Autotrophs • This occurs in autotrophs or producers, organisms that can make their own food.
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Chloroplasts • Chloroplasts are found in plant cells, usually in the leaf. There are half a million chloroplasts per square millimeter of leaf surface.
Chloroplasts Thylakoids are stacked in coin-like stacks called grana. The stroma is the fluid surrounding the thylakoids in the chloroplasts.
leaf’s upper surface photosynthetic cells two outer layers of membrane inner membrane system (thylakoids, all interconnecting bychannels) (see next slide) Fig. 6.3a, p. 94 stroma
Chlorophyll The color of the leaf comes from chlorophyll, the green pigment found in chloroplasts.
Important Pigments • Chlorophyll a • Chlorophyll b • Carotenoids Each absorb light at different wavelengths.
A crystal prism breaks up a beam of light into a spectrum of colors, which are cast across a droplet of water on a microscope slide. Bacteria (white) part of an algal strand stretched out across a microscope slide Colors associated with wavelengths of light (nanometers) Fig. 6.1, p. 92
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Light Reactions- occurs in the thylakoids. Harvests energy from the sun to convert H2O to O2. Hydrogen ions are transported to the Calvin Cycle via NADPH. Dark Reactions (Calvin Cycle)- occurs in stroma. No light required but products from light reactions are needed. Uses excited electrons from light reactions to construct energy-containing sugars using CO2.
sunlight water uptake carbon dioxide uptake ATP ADP + Pi LIGHT DEPENDENT-REACTIONS LIGHT INDEPENDENT-REACTIONS NADPH NADP+ glucose P oxygen release new water in-text, p. 95
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Lab #2 In this lab, you will: • separate plant pigments using chromatography, and • measure the rate of photosynthesis in isolated chloroplasts using DPIP.
Part 4a: Plant Pigment Chromatography • Chromatography is a technique used to separate pigments. • The pigments move at different rates because they are not equally soluble in the solvent and because they are attracted, to different degrees, to the fibers in the paper.
Part 4b:The Light Reactions • During the light reactions, electrons within each photosystem are boosted to a higher energy level, and this energy is used to produce ATP and reduce NADP to NADPH. • In this experiment, a dye-reduction technique is used.
Part 4b:The Light Reactions • In place of NADP, the compound DPIP will be substituted. It will change from blue to colorless. • A machine called a spectrophotometer will be used to measure the light transmittance through the solution.