1. Which of the following is a true statement about microbial metabolism? A. Microbial metabolism only occurs in the presence of oxygen. B. Microbial metabolism does not involve enzymes. C. Microbial metabolism can occur under aerobic or anaerobic conditions. D. All microbes utilize the same metabolic pathways. Answer: C. Microbial metabolism can occur under aerobic or anaerobic conditions. Rationale: Microbes have evolved to survive in various environments, including those without oxygen, by utilizing different metabolic pathways such as fermentation or anaerobic respiration. 2. In the context of microbial metabolism, what is the role of enzymes? A. Enzymes decrease the activation energy of a reaction, speeding up the metabolic process. B. Enzymes provide the energy required for metabolic reactions. C. Enzymes are not specific to substrates and can catalyze any reaction. D. Enzymes increase the activation energy of a reaction. Answer: A. Enzymes decrease the activation energy of a reaction, speeding up the metabolic process. Rationale: Enzymes are biological catalysts that specifically bind to substrates and convert them into products while lowering the activation energy required for the reaction to proceed. 3. What is the end product of glycolysis? A. Glucose B. Lactic acid C. Pyruvate D. ATP Answer: C. Pyruvate Rationale: Glycolysis is the process of breaking down glucose into pyruvate, yielding energy in the form of ATP and NADH, which are used in further metabolic processes. 4. Which of the following best describes oxidative phosphorylation?