Essential Cell Biology Chapter 3 Practice Set Exam Questions with Latest Update

Which statement is true? Choose one: A. The heat released by an animal cell comes from the chemical bond energy present in the food molecules it metabolizes. B. A cell generates order by decreasing the entropy of its surroundings. C. The breakdown of food molecules generates heat, which cells then use to drive the synthesis of large molecules. D. A cell takes in heat from the environment to power its biosynthetic reactions, thereby obeying the second law of thermodynamics. E. Cells obey the first law of thermodynamics but are exempt from the second law. - ANSWER-A. The heat released by an animal cell comes from the chemical bond energy present in the food molecules it metabolizes. Carbon atoms cycle continuously through the biosphere. What is a by-product of cell respiration, and what does this by-product represent? Choose one: CO2; a reduced version of carbon C6H12O6; completely oxidized carbon CO2; completely oxidized carbon C6H12O6; a reduced version of carbon - ANSWER-CO2; completely oxidized carbon What is the origin of the energy that animals acquire by eating plants or other animals? Choose one: A. carbohydrates B. sugars C. fats D. heat E. sunlight - ANSWER-E. sunlight Which of the following statements is not true? Choose one: A. Hydrogenation reactions are oxidations, and dehydrogenation reactions are reductions. B. Oxidation and reduction reactions always occur simultaneously. C. When a carbon atom in a C-H bond has somewhat more than its share of electrons, it is said to be reduced. D. When a sugar molecule is oxidized to CO2 and H2O, the O2 molecules involved in forming the H2O are reduced. - ANSWER-A. Hydrogenation reactions are oxidations, and dehydrogenation reactions are reductions.