BIOL 446 (Biochemistry-1) – Exam 3 with Answers – Jan 2022 (100 out of 100 points)

Questions 1. If a plant in your garden doesn't receive adequate amount of water, which of the following would be most affected? 2. Before the evolution of photosynthesis, the gas that would have ended up as abundant in earth's atmosphere would have been: 3. When does chlorophyll become a toxin? 4. The part of a mitochondrion that structurally compares to the stroma of a chloroplast is the: 5. What is the pathological condition that can happen due to excessive consumption of fructose? Explain with specific metabolic reaction you learned. 6. In order to be able to continue, each turn of the Krebs cycle must regenerate 7. Electron transport system associated with photosystem II produces: 8. What is the specific biochemical reaction that makes bread stale? Explain with the specific chemicals involved. 9. Oxygen is necessary for cellular respiration because oxygen 10. During cell respiration, the pyruvate produced in glycolysis is 11. The cO2 moving into the stroma: 12. In the absence of oxygen, a yeast cell undergoes fermentation and uses 200 molecules of glucose. How much net aTP will be generated? 13. The production of this molecule marks the end of glycolysis and the beginning of cellular respiration 14. What is the role of pH and a specific chemical reaction that prevents esophageal cancer in stomach? 15. At the end of glycolysis, the original carbons of the glucose molecule form: 16. How does galactose toxicity lead to vision problems? 17. What is the metabolic reaction whose disruption causes beriberi? Give the specific reaction involved: 18. Why do you breathe more heavily during exercise? 19. The source of oxygen in photosynthesis reaction is: 20. One of the following chemicals may be absent without affecting photosynthesis: 21. Which metabolic process does insulin fail to inhibit during Type 2 diabetes? Explain the role of specific enzyme and the reaction. 22. From the beginning of glycolysis to the end of the Krebs cycle, what has the cell gained from the breakdown of each molecule of glucose? 23. The energy source in photosynthesis is: 24. Imagine a scientist discovers a mutant plant seedling that appears to lack stomata. What would be the effect of this? 25. How many molecules of water would be used to form two molecules of glucose? 26. You are conducting an experiment to track what happens to the carbons from cO2 molecules used in the light independent reactions of photosynthesis. You add a radioactive tag to the carbons of the cO2 reactants and then collect the products following the reactions. Which products would not be radioactive? 27. A light dependent reaction: 28. In the c3 cycle, the carbon for formation of glucose comes from: 29. In c3 cycle, carbon is fixed by: 30. You are playing a long tennis match and your muscles begin to switch to anaerobic respiration. Which of the following is NOT a bad consequence? 31. Chlorophyll molecules are green because: 32. What are the specific steps in citric acid cycle whose defects lead to development of cancer? 33. The replacement electrons for the reaction center of photosystem II come from 34. The molecule common to both c3 photosynthesis and the process of glycolysis is: 35. One of the following does not occur during the c3 cycle: 36. What results if glucose is metabolized under completely anaerobic conditions? 37. Cyanide causes instant death as it competes with oxygen and it: 38. During which of the following processes is glucose synthesized?