111年 - 111 亞洲大學_學士後獸醫學系招生考試試題：生物化學#113451

1. Histidine has the following pKa values: pK₁ = 1.82, pK₂ = 9.17, = 6.0 Give the net charge of histidine at pH = 12 (A) 0 (B) +1 (C) +2 (D) -1

2. Which amino acid is NOT a building block of proteins? (A) Tryptophan (B) Tyrosine (C) Proline (D) Ornithine

3. The figure below shows the relationship between the titration curve and the acidbase properties of glycine. The key points in the titration are designated I to IV. Which key point of the figure where the average net charge of glycine is 0?
(A) I (B) II (C) III (D) IV

4. Referring to above question 3, which key point of the figure where the glycine exists as a 50:50 mixture of ? (A) I (B) II (C) III (D) IV

5. Referring to above question 3, which region of the figure where glycine has its maximum buffering capacity? (A) I→II (B) I→III (C) II→IV (D) III→IV

6. Which amino acid has two chirality centers? (A) Glycine (B) Tyrosine (C) Threonine (D) Valine

7. Which of the following is a method of isolating ribosomes from mechanically homogenizing (E) coli cells? (A) Edman degradation (B) Polymerase chain reaction (C) Differential centrifugation (D) X-ray crystallography

8. What is the pH of a solution that has an concentration of mol/L? (A) 9 (B) 10 (C) 1 (D) 4

9. Which the following aqueous solution has the lowest pH? (A) 0.1 M lactic acid (pKa = 7.86) (B) 0.1 M acetic acid (pKa = 4.86) (C) 0.1 M succinic acid (pKa = 4.19) (D) 0.1 M formic acid (pKa = 3.75)

10. Which following structural biology method is best suited to obtaining reconstruction of spike (S) protein of SARS-CoV-2 binding with host receptor? (A) Circular dichroism, CD (B) X-ray crystallography (C) Nuclear magnetic resonance, NMR (D) cryo-EM

11. Which the following molecular bonds primary affect the mechanical properties of α-keratin, such as tensile strength and hardness? (A) Disulfide bonds (B) Covalent bond (C) Ionic bond (D) van der Waals force

12. Which the following amino acid primary affects the flexibility of proteins? (A) Phenylalanine (B) Proline (C) Tyrosine (D) Tryptophan

13. Protein 1, 2, 3, and 4 have a binding site for ligand X, respectively. According to the following dissociation constants with ligand X, which protein has the highest affinity for ligand X? (A) Protein 1: (B) Protein 2: (C) Protein 3: (D) Protein 4:

14. Which of the following proteins performs oxygen binding in the blood? (A) Hemoglobin (B) Collagen (C) Albumin (D) Gamma globulin

15. When a polymer of 18-residue forms an α-helix, how many repeats would you expect it to be? (A) 5 (B) 6 (C) 9 (D) 10

16. Which of the following molecules is an enzyme? (A) Fibrin (B) Albumin (C) Trypsin (D) Insulin

17. What type of inhibitor X is this Lineweaver–Burk plot shown?
(A) Competitive inhibition (B) Uncompetitive inhibition (C) Noncompetitive inhibition (D) Irreversible inhibitors

18. Sarin is an extremely toxic synthetic organophosphorus compound. It is a potent inhibitor of acetylcholinesterase. What type of inhibitors does Sarin belong to? (A) Competitive inhibition (B) Uncompetitive inhibition (C) Noncompetitive inhibition (D) Irreversible inhibitors

19. Which following description of the “Michaelis-Menten equation” is correct? (A) (B) (C) High values of correspond to low enzyme affinity for substrate (D) High value of [S] correspond to high enzyme affinity for substrate

20. Which following enzyme reactions do NOT obey Michaelis–Menten kinetics? (A) Double-displacement reactions (B) Allosteric regulations (C) Sequential reactions (D) Ping-pong reactions

21. Which description is NOT correct? (A) Allosteric interactions in Aspartate transcarbamoylase (ATCase) are mediated by large changes in quaternary structure. (B) Chymotrypsinogen is activated by specific cleavage of a single peptide bond. (C) Blood clotting is accomplished by a series of zymogens activation. (D) Glycosylation is a highly effective means of regulating the activities of target proteins.

22. Which of the following characteristics describe glycoproteins? (A) Exclusively located at the cell surface and in the extracellular matrix. (B) Include the heparan sulfate family. (C) May contain N-linked glycosidic bonds. (D) Sulfated glycosaminoglycan chains can only be covalently linked to a Ser residue.

23. What is the major component of vascular plant cell walls? (A) Homopolysaccharide (B) Peptidoglycan (C) Cellulose (D) Glycosaminoglycans

24. Which of the following carbohydrate is heteropolysaccharides? (A) Starch (B) Peptidoglycan (C) Cellulose (D) Glycogen

25. Which of the following carbohydrates is reducing sugar? (A) Fructose (B) Cellulose (C) Starch (D) Sucrose

26. Which description of Apurinic (AP) site in DNA is NOT correct? (A) Apurinic (AP) site is a kind of spontaneous DNA damage. (B) Hydrolysis of the N-glycosyl bond between deoxyribose and purine in DNA creates AP site. (C) AP sites can occur as intermediates in base excision repair. (D) AP site is more thermodynamically stabilizing to a DNA molecule than is a mismatched base pair.

27. Which step of the polymerase chain reaction (PCR) cycle occurs the primers bind to the template? (A) Denaturation (B) Annealing (C) Elongation (D) Hybridization

28. Which nucleosides below contain both purines? (A) A, T (B) C, T, U (C) C, G (D) A, G

29. Which of the following enzymes is NOT required when you clone a foreign DNA fragment into a plasmid? (A) Restriction endonuclease (B) DNA ligases (C) DNA polymerase (D) DNA gyrase

30. Which following method is best suited to identify the protein-protein interaction? (A) Yeast two-hybrid analysis (B) Immunofluorescence (C) qPCR (D) ELISA

31. Which following is NOT omega-3 fatty acid? (A) DHA, 22:6(B) EPA, 20:5 (C) ALA, 18:3 (D) GLA, 18:3

32. The melting points of a series of 18-carbon fatty acids are stearic acid, 69.6°C； oleic acid, 13.4°C； linoleic acid, −5°C； and linolenic acid, −11° C. Which of the above fatty acids has the largest number of cis double bonds? (A) Stearic acid (B) Oleic acid (C) Linoleic acid (D) Linolenic acid

33. How does the food industry increase the melting point of lipids containing fatty acids? (A) Catalytic oxidation (B) Catalytic hydrogenation (C) Catalytic methylation (D) Catalytic phosphorylation

34. Which following molecular is amphipathic? (A) Triacylglycerols (B) Glycerole (C) Cholesterol (D) Succinic acid

35. Which of the following hormone is derived from cholesterol? (A) Estrogens (B) Progesterone (C) Androgens (D) All of the above

36. Which eukaryotic organelles are surrounded by a double membrane? (A) Golgi apparatus (B) Endoplasmic reticulum (C) Mitochondria (D) All of the above

複選題
37. Which description for photosynthesis is NOT correct? (A) The site of photosynthesis in eukaryotes such as green plants and green algae is the chloroplast. (B) In the dark reactions, water is oxidized to produce oxygen, accompanied by the reduction of NAD+ to NADH. (C) The overall reaction pathway of sugar production is cyclic and is called the Krebs cycle. (D) C4 plants grow more quickly than C3 plants.

38. Which codon is stop signals for protein synthesis? (A) UAA (B) UAG (C) UGA (D) All of the above

39. What kind of protein secondary structure is hair α-keratin made of? (A) α-helix (B) β-sheet (C) β-turns (D) Random coils

40. Which description for lipid bilayers is NOT correct? (A) Lipid bilayers form when phospholipids are suspended in oil. (B) Lipids that form bilayers are amphipathic molecules. (C) The hydrophilic regions of lipid bilayers exposed to water and the hydrophobic regions buried in the interior of the sheet. (D) Lipid bilayers close on themselves.

41. Which of the following disease is associated with protein misfolding? (A) Alzheimer’s disease (B) Parkinson's disease (C) Mad cow disease (D) All of the above

42. Which of the following lipoproteins is primarily responsible for transporting cholesterol from surrounding tissues to the liver or steroidogenic organs? (A) VLDL (B) LDL (C) IDL (D) HDL

43. Which description for fatty acid oxidation is NOT correct? (A) Fatty acid oxidation occurs in mitochondria. (B) Fatty acid oxidation is the primary source of energy for many tissues, including the central nervous system and circulating red blood cells. (C) Fatty acid oxidation defects can cause metabolic abnormalities. (D) Fatty acid oxidation is regulated by metabolites and hormones.

44. Which description for the biological membrane is NOT correct? (A) Cell membrane lipid constituents include phospholipids, glycosphingolipids, and cholesterol. (B) Cell membrane protein constituents include glycoproteins and lipid-linked proteins. (C) The constituent lipid and protein molecules are held together by a covalent bond in the membrane. (D) Membranes are fluid structures.

45. Which of the following does NOT cross a cellular membrane without transporters or channels? (A) (B) (C) (D) All of the above

46. Which of the following is a second messenger molecule that can activate protein kinase A (PKA) in eukaryotes? (A) Cyclic AMP (B) Cyclic GMP (C) Inositol 1,4,5-trisphosphate (IP₃) (D) Diacylglycerol (DAG)

47. Which of the following metabolisms can NOT be regulated by protein kinase A (PKA)? (A) Enhance lipolysis in adipocyte (B) Enhance glycogenesis in skeletal muscle (C) Enhance glycogenolysis in liver (D) Enhance gluconeogenesis in liver

48. Which ions are required for the glucose symporter transporter in the intestinal epithelium? (A) (B) (C) (D)

49. How many fatty acid molecules do a phosphatidylcholine (PC) of plasma membrane have? (A) 1 (B) 2 (C) 3 (D) None of above

50. Which of the following molecule does NOT affect membrane fluidity? (A) Sphingomyelin (B) Triglyceride (C) Cholesterol (D) Glycosphingolipids

51. Which description for receptor tyrosine kinases (RTK) is NOT correct? (A) RTKs is a family of plasma membrane receptors with protein kinase activity. (B) RTKs transduce extracellular signals through a mechanism similar to G protein-coupled receptors (GPCRs). (C) RTKs have a ligand-binding domain on the extracellular face of the plasma membrane. (D) RTKs have an enzyme active site on the cytoplasmic face.

52. Which description for G protein-coupled receptors (GPCRs) is NOT correct? (A) G protein-coupled receptors (GPCRs) have seven transmembrane beta-sheets domains. (B) GPCRs act through heterotrimeric G proteins. (C) GPCRs are found only in eukaryotes, including yeast, choanoflagellates, and animals. (D) GPCRs are involved in many diseases.

53. Which receptor of signal-transduction pathways is involved in glucose uptake regulation? (A) Sialic acid receptor (B) Insulin receptor (C) β-Adrenergic receptor (D) EGF receptor

54. Which of the following is NOT pentose phosphate pathway (PPP) product in oxidative nonreversible phase? (A) Ribose-5-phosphate (B) NADH (C) NADPH (D) CO₂

55. Which one of the following molecules is NOT the second messenger in the phosphoinositol signaling pathway? (A) Calcium ions (B) Inositol 1,4,5-trisphosphate (IP₃) (C) Cyclic adenosine monophosphate (cAMP) (D) Diacylglycerol (DAG)