9. The pentose phosphate pathway is an important source of_______, and for ________, an essential precursor for ATP, NAD , FAD, CoA, DNA and RNA.
(A) ATP;NADH
(B) NADH; NADPH
(C) NADPH; ribose-5-phosphate
(D) ribose-5-phosphate; ATP
(E) all are true

5. All are characteristic of the conversion of glucose to lactate EXCEPT: (A) anaerobic pathway ay with no net oxidation. (B) "primed" by ATP phosphorylation. (C) located in the cytosol. (D) approximately 50% efficient in erythrocytes. (E) net production of four ATP per glucose. while in anaerobic glycolysis, pyruvate is phosphorylation, and NADH-dependent ATP

6. All are important reaso sons to phosphorylate glucose in the first step of glycolysis EXCEPT: (A) the large positive free energy is important in getting the pathway started. (B) glucose-6-phosphate has a negative charge preventing transport out of the cell. (C) the concentration of free glucose in the cell is lowered favoring influx of glucose. (D) phosphorylation keeps the glucose in the cell. (E) regulatory control can be imposed only at a reaction not at equilibrium.

7. Substrate-level phosphorylation occurs in glycolysis in the reaction catalyzed by_______and belongs to class of enzymes. (A) phosphoglycerate kinase; transferase (B) hexokinase; transferase (C) phosphofructokinase; transferase (D) glucokinase; transferase (E) glyceraldehyde-3-phosphate dehydrogenase; oxidoreductase

8. The only reaction of the citric acid cycle that provides substrate-level phosphorylation is catalyzed by: (A) malate dehydrogenase. (B) citrate synthase. (C) isocitratc dehydrogenase. (D) succinyl-CoA synthetase. (E) nucleotide triphosphate kinase. 

10. Which of the following statements about the light r reactions of photosynthesis is true? (A) There are two distinct photosystems, linked together by a mechanism similar to electron transport. (B) The source for electrons is located in the stroma of the thylakoid. (C) The Mn complex is the primary electron acceptor and is located on photosystem I. (D) The ultimate electron donor is molecular oxygen. (E) Plastoquinone is a fixed electron transporter in the system located in the inner membrane.

11. The primary storage form of lipid is__________ and it is normally stored in the__________ . (A) phospholipid； liver (B) cholesterol； muscles (C) monoacyiglycerol； adipocytes (D) triacylglycerols； adipocytes (E) triacylglycerols； liver

12. In the citric acid cycle, acetyl-CoA reacts with_________to produce______. (A) fumarate; -kctoglutarate (B) oxaloacetate; citrate (C) citrate; isocitrate (D) succinyl-CoA; oxaloacetate (E) malate; cis-aconitate

13. What is the committed step in fatty acid biosynthesis? (A) Binding of the fatty acyI group to the acyl carrier protein. (B) Synthesis of malonyl CoA. (C) Transacylase reaction. (D) The formation of acetoacetyl-ACP. (E) None of the above.

14. Organisms capable of atm nospheric nitrogen fixation include: (A) some bacteria and archaca. (B) higher eukaryotic organisms, such as mammals. (C) all plants. (D) fungi, including yeasts and molds. (E) None of the above.

15. The brain normally uses_________as its source of metabolic energy, but during starvation _may be the major source of energy. (A) glucose； ketone bodies (B) ketone bodies； fatty acids (C) fatty acids； amino acids (D) amino acids； glucose (E) all are true