General Metabolism and Glycolysis PDF

**1. General Overview: Macromolecule Metabolism** 1. **Which of the following macromolecules is primarily broken down in the glycolytic pathway?** - A\) Proteins - B\) Nucleic acids - C\) Lipids - D\) Carbohydrates\ **Answer:** D) Carbohydrates 2. **Which...

**1. General Overview: Macromolecule Metabolism** 1. **Which of the following macromolecules is primarily broken down in the glycolytic pathway?** - A\) Proteins - B\) Nucleic acids - C\) Lipids - D\) Carbohydrates\ **Answer:** D) Carbohydrates 2. **Which metabolic process is responsible for synthesizing new proteins in the body?** - A\) Glycolysis - B\) Lipogenesis - C\) Protein synthesis - D\) Gluconeogenesis\ **Answer:** C) Protein synthesis 3. **Which of the following is NOT a major end product of lipid catabolism?** - A\) Fatty acids - B\) Amino acids - C\) Glycerol - D\) Acetyl-CoA\ **Answer:** B) Amino acids 4. **Nucleic acid metabolism involves the synthesis and breakdown of:** - A\) Proteins and peptides - B\) Lipids and cholesterol - C\) DNA and RNA - D\) Carbohydrates and glycogen\ **Answer:** C) DNA and RNA **2. Carbohydrate Metabolism: Glycolysis** 5. **What is the net gain of ATP molecules produced per molecule of glucose during glycolysis?** - A\) 1 ATP - B\) 2 ATP - C\) 4 ATP - D\) 6 ATP\ **Answer:** B) 2 ATP 6. **Which enzyme catalyzes the conversion of glucose to glucose-6-phosphate in the first step of glycolysis?** - A\) Hexokinase - B\) Phosphofructokinase - C\) Pyruvate kinase - D\) Lactate dehydrogenase\ **Answer:** A) Hexokinase 7. **In the process of glycolysis, which molecule acts as the final electron acceptor to form lactate in anaerobic conditions?** - A\) Oxygen - B\) NAD+ - C\) NADH - D\) Pyruvate\ **Answer:** D) Pyruvate 8. **Which step in glycolysis is considered the 'rate-limiting step'?** - A\) Glucose to glucose-6-phosphate - B\) Fructose-6-phosphate to fructose-1,6-bisphosphate - C\) Glyceraldehyde-3-phosphate to 1,3-bisphosphoglycerate - D\) Phosphoenolpyruvate to pyruvate\ **Answer:** B) Fructose-6-phosphate to fructose-1,6-bisphosphate 9. **During glycolysis, glucose is ultimately broken down into:** - A\) Two molecules of acetyl-CoA - B\) Two molecules of pyruvate - C\) Two molecules of glycerol - D\) One molecule of lactic acid\ **Answer:** B) Two molecules of pyruvate 10. **Which enzyme in glycolysis catalyzes the substrate-level phosphorylation that produces ATP?** - A\) Hexokinase - B\) Phosphofructokinase - C\) Pyruvate kinase - D\) Aldolase\ **Answer:** C) Pyruvate kinase **3. Integration of Metabolic Pathways** 11. **In which cellular organelle does glycolysis take place?** - A\) Mitochondria - B\) Nucleus - C\) Cytoplasm - D\) Endoplasmic reticulum\ **Answer:** C) Cytoplasm 12. **Which metabolic pathway is responsible for generating glucose from non-carbohydrate sources?** - A\) Glycolysis - B\) Gluconeogenesis - C\) Citric Acid Cycle - D\) Lipogenesis\ **Answer:** B) Gluconeogenesis 13. **In aerobic conditions, pyruvate from glycolysis is converted into:** - A\) Lactate - B\) Ethanol - C\) Acetyl-CoA - D\) Oxaloacetate\ **Answer:** C) Acetyl-CoA **4. Energy and Regulation in Glycolysis** 14. **How many NADH molecules are produced per molecule of glucose during glycolysis?** - A\) 1 NADH - B\) 2 NADH - C\) 4 NADH - D\) 6 NADH\ **Answer:** B) 2 NADH **5. Lipid, Protein, and Nucleic Acid Metabolism Overview** 15. **Which pathway involves the breakdown of triglycerides into fatty acids and glycerol?** - A\) Glycolysis - B\) Lipolysis - C\) Lipogenesis - D\) Protein synthesis\ **Answer:** B) Lipolysis 16. **What is the main purpose of the urea cycle in amino acid metabolism?** - A\) To produce energy - B\) To synthesize proteins - C\) To excrete nitrogen - D\) To generate glucose\ **Answer:** C) To excrete nitrogen 19. **The breakdown of glucose in glycolysis produces pyruvate. In the presence of oxygen, pyruvate enters which cycle?** - A\) Urea cycle - B\) Cori cycle - C\) Citric acid cycle (Krebs cycle) - D\) Calvin cycle\ **Answer:** C) Citric acid cycle (Krebs cycle) 20. **Which coenzyme is regenerated during the conversion of pyruvate to lactate under anaerobic conditions?** - A\) NAD+ - B\) FAD - C\) NADH - D\) Coenzyme A\ **Answer:** A) NAD+ 21. **Which of the following molecules provides feedback inhibition to hexokinase in glycolysis?** - A\) Glucose - B\) ATP - C\) Glucose-6-phosphate - D\) ADP\ **Answer:** C) Glucose-6-phosphate 22. **Which enzyme in glycolysis catalyzes the cleavage of fructose-1,6-bisphosphate into two three-carbon molecules?** - A\) Hexokinase - B\) Aldolase - C\) Enolase - D\) Pyruvate kinase\ **Answer:** B) Aldolase 23. **The final step of glycolysis, catalyzed by pyruvate kinase, produces pyruvate and:** - A\) ADP - B\) NADH - C\) ATP - D\) CO₂\ **Answer:** C) ATP **7. Lipid Metabolism** 24. **During fatty acid oxidation, each cycle of beta-oxidation produces which of the following?** - A\) Acetyl-CoA, NADH, and FADH₂ - B\) ATP and NADH - C\) Glycerol and ATP - D\) Amino acids and water\ **Answer:** A) Acetyl-CoA, NADH, and FADH₂ 25. **Which of the following is a precursor molecule for triglyceride synthesis?** - A\) Glucose - B\) Pyruvate - C\) Glycerol - D\) Lactate\ **Answer:** C) Glycerol **8. Metabolic Regulation** 26. **The presence of high levels of which molecule signals cells to start glycogen synthesis?** - A\) Glucagon - B\) Insulin - C\) Epinephrine - D\) Cortisol\ **Answer:** B) Insulin 27. **Which hormone stimulates the breakdown of glycogen to glucose in response to low blood sugar?** - A\) Insulin - B\) Glucagon - C\) Epinephrine - D\) Cortisol\ **Answer:** B) Glucagon