108年 - 108 國立中央大學_碩士班考試入學試題_生命科學系分子與細胞生物組(一般生、在職生)：生物化學#126357

1. Which of the following reagents is commonly used to stain a nucleic acid gel? (A) bromophenol blue (B) EtBr (C) ninhydrin reagent (D) CNBr (E) Coomassie Brilliant Blue.

2. A protein is composed of 200 amino acids. What is its approximate molecular weight? (A) 10 (B) 22 (C) 100 (D) 220 (E) 3,300 kDa.

3. The concentration of a nucleic acid can be determined by its UV-Vis absorbance at __ nm. (A) 190 (B) 200 (C) 240 (D) 260 (E) 280.

4. The Western blotting technique is used for the measurement of (A) protein (B) DNA (C) RNA (D) lipid (E) carbohydrates.

5. Which of the following amino acids has only one codon? (A) Arg (B) Ala (C) Val (D) Met (E) His.

6. Dithiothreitol (DTT) is a reducing agent that interacts with proteins by disrupting which of the following? (A) Hydrogen bonds (B) Disulfide bridges (C) Hydrophobic interactions (D) Salt bridges (E) Covalent bonds.

7. The most abundant lipid in the human body is (A) Waxes (B) Triacylglycerol (C) Fatty acids (D) Cholesterol (E) Glycerol.

8. Which amino acid commonly serves as either a general acid or a general base in the enzyme mechanism? (A) serine (B) cysteine (C) glutamic acid (D) arginine (E) histidine

9. How many turns of the fatty acid spiral are needed to "process" a C₁₉ fatty acid molecule? (A) 6 (B) 7 (C) 8 (D) 10 (E) 14

10. NADPH can be produced from (A) TCA cycle (B) glycolysis (C) pentose phosphate pathway (D) fatty acid oxidation (E) lipid biosynthesis.

11. In one catalytic cycle, the Na⁺/K⁺ ATPase transporter transports: (A) 2 Na⁺ out, 3 K⁺ in, and converts 1 ATP to ADP + Pi. (B) 2 Na⁺ out, 3 K⁺ in, and converts 1 ADP + Pi to ATP. (C) 3 Na⁺ in, 2 K⁺ out, and converts 1 ATP to ADP + Pi. (D) 3 Na⁺ out, 2 K⁺ in, and converts 1 ADP + Pi to ATP. (E) 3 Na⁺ out, 2 K⁺ in, and converts 1 ATP to ADP + Pi.

12. What are the ẞ-oxidation products of stearic acid (18:0)? (A) 9 acetyl-CoA, 9 NADH, 9 FADH2, 2 ATP used for activation (B) 9 acetyl-CoA, 8 NADH, 8 FADH2, 2 ATP used for activation (C) 9 acetyl-CoA, 9 NADH, 9 FADH2, 1 ATP used for activation (D) 9 acetyl-CoA, 8 NADH, 8 FADH2, 1 ATP used for activation (E) 9 acetyl-CoA, 8 NADH, 7 FADH2, 2 ATP used for activation.

13. What are the ẞ-oxidation products of oleic acid (18:1^△9) and how many ATP equivalents are required for activation? (A) 8 acetyl CoA, 8 NADH, 7 FADH2, 1 ATP equivalents (B) 9 acetyl CoA, 8 NADH, 7 FADH2, 2 ATP equivalents (C) 9 acetyl CoA,7 NADH, 7 FADH2, 1 ATP equivalents (D) 8 acetyl CoA, 7 NADH, 6 FADH2, 2 ATP equivalents (E) 8 acetyl CoA, 8 NADH, 8 FADH2, 1 ATP equivalents.

14. Which of the following organisms is a prokaryote? (A) Saccharomyces cerevisiae (B) Caenorhabditis elegans(C) Escherichia coli (D) Drosophila melanogaster (E) Arabidopsis thaliana

15. Which scientist made a significant contribution to the technology of DNA sequencing? (A) K. B. Mullis(B) F. Sanger (C) A. D. Hershey and M. Chase (D) S. B. Prusiner (E) J. D. Watson and H. C. Crick.

16. Which of the following reactions is not located in the mitochondria? (A) β-oxidation (B) cholesterol biosynthesis (C) ketone body synthesis (D) tricarboxylic acid cycle (E) electron transport and oxidative

17. Which amino acid listed below can serve as the precursor for dopamine? (A) Val (B) Leu (C) Trp (D) Thr
(E) Tyr

18. A deficiency in folic acid will not impair the metabolism of which of the following amino acids? (A) Met(B) Val (C) Ser (D) Ala (E) His

19. Hydroxymethylglutaryl-CoA reductase (A) is the rate-limiting enzyme for triglyceride synthesis (B) is the
rate-limiting enzyme for estrogen synthesis (C) is activated by lovastatin (D) uses NADH as the cofactor
(E) is inhibited by cholesterol.

20. Which of the following descriptions about the Michaelis-Menten rate equation is incorrect? (A) Км measures the substrate concentration at which the reaction rate is V_max/2 (B) k_cat is the turnover number that measures the rate of the catalytic process (C) The ratio k_cat/K_M is a convenient measure of enzyme efficiency (D) A competitive inhibitor increases the apparent K_M. (E)V_max = k_cat/K_M

21. Non-steroidal anti-inflammatory drugs (NSAIDS) like aspirin and ibuprofen act by blocking production of:(A) vitamin D (B) prostaglandins (C) sphingolipids (D) glycerol (E) none of the above.

22. When a bacterium such as E. coli is shifted from a warmer growth temperature to a cooler growth temperature, it compensates by: (A) increasing its metabolic rate to generate more heat (B) synthesizing thicker membranes to insulate the cell. (C) putting longer-chain fatty acids into its membranes (D) shifting from aerobic to anaerobic metabolism (E) putting more unsaturated fatty acids into its membranes

23. After drinking of coke, the major monosaccharides absorbed into the blood are (A) glucose (B) fructose (C) glucose and fructose (D) glucose and galactose (E) galactose, glucose, and fructose.

24. Which of the following is not a reducing sugar? (A) Glyceraldehyde (B) Glucose (C) Fructose (D) Lactose
(E) Sucrose

25. The pK_as of phosphoric acid are 2.1, 6.9, and 12.4. The ionic form that predominates at pH 7.5 is: (A) H₃PO₄ (B) H₂PO₄^- (C) HPO_4^2- (D) PO₄^3- (E) None of the above.

26. Which of the following is not involved in the process of assisted folding of proteins?(A) Heat shock proteins (B) Peptide bond hydrolysis (C) Chaperonins (D) Disulfide interchange
(E) Peptide bond isomerization.

27. The_______ molecules are not amphipathic. (A) phophotidyl choline (B) phosphotidyl ethanolamin (C) cholesterol (D) sphingomyolin (E) none of the above

28. The binding of one O₂ to one subunit in the hemoglobin tetramer (a2ẞ2) increases the binding affinity of subsequent O₂ binding to other subunits is achieved via the ________ effect. (A) allosteric (B) quantum (C) hydrophobic (D) hydrophilic (E) cooperative

29. DNA of the ________form runs the slowest on the agarose gel. (A) supercoiled (B) linear (C) partially nicked (D) inter-wound (E) circular

30. Fumarate from the urea cycle is converted to malate and then to________, which can be used for gluconeogenesis. (A) citrate (B) succinate (C) oxaloacetate (D) a-ketoglutarate (E) pyruvate

31. A molecule that signals vasodilation is_______ , which is synthesized from the precursor_______ .(A) nitric oxide (NO)/citrulline (B) nitric oxide (NO)/arginine (C) nitrous oxide (N₂O)/arginine(D) nitrous oxide (N₂O)/citrulline (E) none of the above

32. Which of the following metabolic pathways is carried out only in the liver?(A) ogen storage (B) pentose phosphate pathway (C) fatty acid synthesis (D) triacylglycerol synthesis
(E) ketogenesis

33. Ketone bodies are produced in the________and used by the________only under conditions such as a prolonged fast. (A) liver/heart (B) liver/skeletal muscle (C) liver/brain (D) kidneys/heart (E) kidneys/brain

34. 39. Which of the lipoproteins is responsible for removing cholesterol from cells?(A) Chylomicron (B) VLDL (C) LDL (D) VHDL (E) HDL

35. Which of the following do NOT correctly pair a hormone with its function? (A) ACTH-promotes production of thyroxin (B) insulin-regulates metabolism and blood glucose (C) FSH-stimulates processes within the gonads (D) calcitonin -regulates plasma Ca^²+ (E) prolactin-stimulates milk production.

 (1) KM

(2) Vmax

(3) kcat (9 points)

(1) structural component of plant cell walls

(2) blood clotting

(3) Ca²⁺ and phosphate metabolism

(4) carbohydrate storage in animal liver

(5) mediates pain and inflammation

(1) Leptin

(2) Aquaporins

(3) Integrins

(4) Calmodulin

(5) Carnitine

(6) Ubiquitin

(1) has the greatest UV light absorbance at 280 nm?

(2) contains the largest number of hydrophobic side chains.

(3) contain sulfur atom.

(4) is most negatively charged at pH 7.

(5) is most positively charged at pH 7.

(6) contain the aromatic side chain