49. Which of following is NOT a second messenger in signal transduction?
(A) proton
(B) cAMP
(C) Ca2+
(D) inositol triphosphate (IP3)
(E) diacylglycerol (DAG)

45. Which of the following statements about drugs is FALSE? (A) Taxol inhibits cancer cells by preventing microtubule depolymerization. (B) Tamoxifen inhibits cancer cells by blocking the function of estrogen receptor. (C) RU486 induces abortion by blocking the function of estrogen receptor. (D) Erythromycin inhibits the growth of bacteria by blocking their ribosomes. (E) Chloramphenicol inhibits the growth of bacteria by blocking their ribosomes.

46. Which of the following sugars contain ketone group? (A) glyceraldehyde (B) ribose (C) glucose (D) fructose (E) galactose

47. Which of the following proteins have quaternary structure? I. Methionine II. Lysozyme III. Collagen IV. Hemoglobin (A) I and II (B) III and IV (C) I, II, and IV (D) II, III, and IV (E) II and III

48. Endomembrane system includes following organelles, except ______. (A) nuclear envelope (B) endoplasmic reticulum (ER) (C) Golgi apparatus (D) mitochondria (E) lysosome

50. All of the enzymes catalyze reactions to produce NADH , FADH2 or ATP in citric acid cycle, except ______. (A) isocitrate dehydrogenase (B) α-ketoglutarate dehydrogenase (C) succinyl-CoA synthetase (D) succinate dehydrogenase (E) citrate synthetase

51. Which of the following molecule does NOT participate in oxidative phosphorylation? (A) proton (B) Ca2+ (C) ubiquinone (Q) (D) cytochrome c (cyt c) (E) ADP

52. Which of the following statements about cell cycle is FALSE? (A) Cyclin is degraded during G1. (B) Synthesis of cyclin begins in S phase. (C) Cyclin combines with Cdk to produce maturation-promoting factor (MPF). (D) MPF promotes mitosis by phosphorylating various proteins. (E) MPF’s activity peaks during prophase of M phase.

53. Which of the following statements about inherited disorders is FALSE? (A) Cystic fibrosis, a recessive disease, is caused by the defect of Cl- transporter. (B) Tay-Sachs disease, a dominate disease, is caused by the defect in mitochondria. (C) Phenylketonuria, a recessive disease, is caused by inability to metabolized phenylalanine. (D) Huntingon’s disease, a dominate disease, is a neuron degenerative disease. (E) Sickle-cell disease caused by T to A substitution results in defect of hemoglobin.

複選題54. Which of the following statements about bacterial replication fork is FALSE? (A) Helicase breaks and unwinds parental DNA. (B) Primase synthesizes DNA primers. (C) DNA polymerase III synthesizes leading strand. (D) DNA polymerase I removes the primers. (E) DNA ligase joins the Okazaki fragments.

55. Which of the following statements about the molecules of appetite regulation is FALSE? (A) Hormone ghrelin is secreted by stomach to trigger feelings of hunger. (B) Hormone insulin is secreted by pancreas to suppress appetite by brain. (C) Hormone leptin is secreted by adipose to suppress appetite. (D) Hormone PYY is secreted by small intestine to suppress appetite. (E) Hormone syndecan is secreted by hypothalamus to trigger appetite.