Chapter 8 Photosynthesis Class Activity Notes

PHOTOSYNTHESIS INSTRUCTIONS Use complete sentences to answer the questions below. 1. Write down the formula for photosynthesis. Make sure to label the reactants and the products. CO2 + H2O - C6H12O6 + O2 2. The carbon source to make glucose is: CO2 from water 3. The hydrogens present in glucose come from the oxidation of: NADH, FADH 4. The oxigen released into the environment comes from: Water molecule 5. Label the chloroplast include 1. Thylakoids, 2. stroma, 3. Light reaction, 4. Calvin cycle. 3 2 1 4 6. On the diagram below - identify the two reactions of photosynthesis? light Kreb’s Cycle photosynthesis energy CO2 NADH FADH 7. What are the products of the light reaction? Write you answer here and also place your answer in the diagram above. Charbohydrates and CO2 8. Why are pigments required for the light reaction? Chloroplast are needed to capture light energy from the sun. 9. What are the products of the calvin cycle? Write you answer here and also place your answer in the diagram above. NADH2, FADH2 10. Can the calvin cycle take place without the light reaction? Explain. No, the calvin cycle can not take place without a light reaction. Gylcolysis can not take place without a light reaction and that comes before the calvin cycle. 11. The product of the Calvin cycle is a triose-phosphate sugar that is either exported from the chloroplast or used to regenerate RUBP. a. How many times must each of the reactions in the Calvin cycle take place in order to complete the synthesis of one 3-carbon triose phosphate sugar molecule? A. 1 B. 2 C. 3 D. 6 12. The reactions of the Calvin cycle used to be referred to as the “dark reactions” of photosynthesis, implying that light was not required for this pathway to incorporate CO 2 into carbohydrate. However, in the absence of light, the Calvin cycle shuts down. b. Which parts of the Calvin cycle would be impacted first by the absence of light energy? A. the carboxylation of RuBP B. the regeneration of RuBP C. the synthesis of hexose sugars D. the reduction of 3-phosphoglycerate 13. What is the initial carbon input in the Calvin cycle? A. CO2 B. triose phosphate C. C6H12O6 D. rubisco 14. Why is the absorption and capture of light energy by chlorophyll molecules in plants much more efficient than its absorption and capture by a solution of chlorophyll molecules in the lab? A. An artificial light source is used in the lab. B. In the plant, other accessory proteins are produced. C. In the plant, the energy is transferred between molecules. D. Electrons are more readily available in solution. 15. In the evolution of photosynthesis, which of these processes happened first? A. mitochondrial membrane structure B. chloroplast membrane structure C. the acquisition of two photosystems by cyanobacteria D. endosymbiosis 16. Some of the intermediates in the biosynthesis of chlorophyll are themselves capable of absorbing light energy. A. true B. false Instructions: Complete the following model of photosynthesis in which the two main processes are represented by boxes and with arrows that have the following meanings: : sunlight/photons : energy management molecules (ATP and electron carriers) : inputs and outputs other than energy management molecules 17. Step 1. Label each box and each arrow. CO2 Sunlight Photosynthesis NADPH Glucose H2O O2 18. Step 2. ATP and the electron carriers shown above as open arrows are in their high-energy state(s). Using dashed arrows ( ), show where these molecules flow when returned to their low-energy state(s). ATP