Figure 10-1 Light energy Sunlight H2OH2OO2O2 Light-dependent reactions ATP, NADPH Chemical energy CO 2 Calvin cycle (CH 2 O) n Chemical energy

Figure 10-2 Leaves contain millions of chloroplasts. Chloroplasts are highly structured, membrane-rich organelles. Outer membrane Chloroplasts Cell Inner membrane Thylakoids Granum Stroma

Figure Leaf surfaces contain stomata. Carbon dioxide diffuses into leaves through stomata. Guard cells Pore Stoma CO 2 Extracellular space Photosynthetic cells O2O2 H2OH2O Leaf surface Interior of leaf Leaf surface

Figure 10-4 Higher energy Wavelengths (nm) Gamma rays X-rays Ultra- violet Infrared Micro- waves Radio waves Shorter wavelength Visible light Longer wavelength Lower energy nm

Figure 10-6a Different pigments absorb different wavelengths of light. Chlorophyll b Chlorophyll a Carotenoids Chlorophylls absorb blue and red light and transmit green light Carotenoids absorb blue and green light and transmit yellow, orange, or red light

Figure Reaction center Fluorescence Heat Photon e–e– e–e– Electron acceptor Chlorophyll molecules in antenna complex Reaction center Chlorophyll molecule Lower Higher Energy of electron RESONANCEFLUORESCENCEREDUCTION/OXIDATION or e–e– Electron drops back down to lower energy level; heat and fluorescence are emitted. Electron is transferred to a new compound. Energy in electron is transferred to nearby pigment.

Figure 10-1 Light energy Sunlight H2OH2OO2O2 Light-dependent reactions ATP, NADPH Chemical energy CO 2 Calvin cycle (CH 2 O) n Chemical energy

Figure NADPH The Calvin cycle has three phases. 3 ATP + 3 CO 2 Regeneration: 5 G3P + 3 RuBP 3 ATP Fixation: Reduction: 3 RuBP 6 3-phosphoglycerate + 6 ATP 6 G3P 6 NADPH 6 ADP The reaction occurs in a cycle. All three phases of the Calvin cycle take place in the stroma of chloroplasts 3 CO 2 RuBP 3 ADP + 3 P i Carbons are symbolized as red balls to help you follow them through the cycle 3 PP 6P 1 G3P G3P 5 G3P 6 P 6 ATP 3-phosphoglycerate 6 H P i 6 NADP + Fixation of carbon dioxide Regeneration of RuBP from G3P Reduction of 3-phospho- glycerate to G3P + +

Figure Starch Glucose subunit Up to 1000 or more monomers Glucose subunit Fructose subunit Sucrose Glucose subunit Starch is a storage product Sucrose is readily transported

Figure Leaf surfaces contain stomata. Carbon dioxide diffuses into leaves through stomata. Guard cells Pore Stoma CO 2 Extracellular space Photosynthetic cells O2O2 H2OH2O Leaf surface Interior of leaf Leaf surface

Figure Reaction with carbon dioxide during photosynthesis : RuBP + CO 2 two 3-phosphoglycerate used in Calvin cycle Reaction with oxygen during “photorespiration” : RuBP + O 2 one 3-phosphoglycerate + one 2-phosphoglycolate used in Calvin cycle when processed, CO 2 is released and ATP is used

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