39. Which of the following reactions is most likely catalyzed by a   ligase  ?
(A) A+ H₂O ←→P+Q
(B) A + B + ATP ←→ P + ADP +
(C) A ←→ P+Q
(D) A + ←→P + NADH
(E) A + ATP ←→ P + ADP

35. Defects in which of the following enzyme will NOT cause hyperammonemia. (A) Cabomoyl phosphate synthetase I (B) Ornithine permease (C) Arginase (D) N-acetylglutamate synthase (E) Ornithine transcarbamoylase

36. Which enzyme releases the amide nitrogen of glutamine to form glutamate? (A) Glutamate dehydrogenase (B) Glutamate pyruvate transaminase (GPT) (C) Glutaminase (D) Glutamate oxaloacetate transaminase (GOT) (E) Glutamine synthetase

37. What property do biotin, tetrahydrofolate and S-adenosylmethionine have in common? (A) They bind streptavidin (B) They transfer single nitrogen (C) They transfer single carbon (D) They are amino acid derivatives (E) They are enzymes

38. Which of the amino acid is NOT glucogenic? (A) Isoleucine (B) Arginine (C) Lysine (D) Tryptophan (E) Aspartatic acid

40. To measure the "rate" of an enzymatic reaction, you need to plot (A) "substrate concentration" vs "time" (B) "initial rate" vs "substrate concentration" (C) "initial rate" vs "time" (D) "initial rate" vs "product concentration" (E) "free enzyme concentration" vs "time"

41. When [S] increases from 2Kᴍ to 4Kᴍ, the initial velocity (Vo) of an enzyme catalyzed reaction increases by a factor of _____ (Assuming this enzyme follows the Michaelis-Menton kinetics.) (A) 0.9 (B) 1.0 (C) 1.1 (D) 1.2 (E) 1.4

42. Inhibitor "X" was found to decrease the Vmax (maximum velocity) of an enzymatic reaction. Therefore, "X" can be classified as a _____ (A) competitive inhibitor (B) uncompetitive inhibitor (C) mixed inhibitor (D) uncompetitive inhibitor or mixed inhibitor (E) competitive inhibitor or mixed inhibitor

43. The ligands for peroxysome proliferator-activator receptor (PPAR) belong to which of the following categories. (A) protein (B) vitamin (C) fatty acid (D) amino acid (E) carbohydrate

44. Cholera toxin, a protein produced by a gram-negative bacterium vibrio cholerae, is responsible for the characteristic symptoms of cholera: extensive loss of body water and Na⁺ through continuous, debilitating diarrhea. If body fluid and Na⁺ are not replaced, severe dehydration results； untreated, the disease is often fatal. What is the effect of cholera toxin in the intestinal cells? (A) Increase GTP hydrolysis. (B) Persist activation of G protein. (C) Increase the degradation of cGMP. (D) Increase the rate of phophatidylinositol turnover. (E) Open the chloride channels on the membrane of intestinal cells. 

45. According to the description, which of the following compounds could illicit proliferation signaling in smooth muscle cells? (A) thrombin (B) vitamin K (C) interferon (D) cholesterol (E) retinoic acid