Converting Light Energy into Chemical Energy Photosynthesis Converting Light Energy into Chemical Energy

I. Photosynthesis Background Photosynthesis drives and supports all life on earth (except at hydrothermal vents). Understanding this important reaction will help us better understand the limits and effects of human and other populations on our planet. Sun provides energy-> Plants make food-> Consumers eat plants-> Consumers thank plants!

I. Photosynthesis B. Location Plant Cell The reactions of photosynthesis occur within plant cells in the chloroplast. Chloroplasts contain pigments called chlorophyll, which capture light. C. Products & Reactants of Photosynthesis Light Energy Sugar + O2 CO2 + H2O

D. Overview of Photosynthesis - In the chloroplasts of photosynthetic organisms, the energy of sunlight is transformed into the energy stored in the chemical bonds of carbohydrates (glucose) CO2 H2O Light Chloroplast Captured by rubisco enzyme O2 Other materials Calvin Cycle: Chlorophyll absorbs light for light reactions Dark (Light- Independent) Reactions Energy: Light- Dependent Reactions H+ ions Dark Reactions ATP NADPH Sugar (Glucose) C6H12O6 Q: What happens to the glucose after it is made by the plant cell?

E. A Closer Look at Photosynthesis 1. Light Reactions (Light Dependent) Light energy, absorbed by chlorophyll, splits water to store chemical energy (ATP), releasing hydrogen and oxygen H2O + light  ATP (energy) + H+ + O2 2. Dark Reactions (Light Independent) The energy generated in the light reaction converts carbon dioxide and hydrogen ions into sugar (glucose) ATP(energy) + H+ + CO2  C6H12O6 (+ ADP +P) Q: What is ATP?

ATP: adenosine triphosphate the form of stored energy that is useable by cells Energy is stored and/or released when bonds between the phosphates are formed or broken