68. Ketone bodies are produced by file β-oxidation of an excess of acetyl-CoA. Which of the followings are ketone bodies?
(A) ①②③
(B) ①③④
(C) ②④
(D) ③④
(E) ②④⑤

69. Many biomolecules are derived from amino acid precursors. Serotonin and dopamine are synthesized from ____and____ , respectively. (A) histidine； tyrosine (B) phenylalanine； tryptophan (C) tryptophan； tyrosine (D) histidine； tryptophan (E) tryptophan； histidine

70. Several nucleotide bases undergo spontaneous loss of their exocyclic amino groups (deamination). Deamination of the nucleotide bases cytosine and 5‑methylcytosine yields nucleotide bases:(A) hypoxanthine and xanthine, respectively.(B) uracil and thymine, respectively.(C) uracil only.(D) uracil and hypoxanthine, respectively.(E) thymine and uracil, respectively.

71. If a cell were unable to synthesize or obtain tetrahydrofblic acid (H4 folate), it would probably be deficient in the biosynthesis of: (A) isoleucine (B) leucine (C) lysine (D) methionine (E) serine

72. Which of the following statements explains why allopurinol is able to prevent gout? (A) It binds to uric acid thus preventing the fonnation of uric acid crystals. (B) It acts as a diuretic to increase the elimination of uric acid. (C) It inhibits tiie production of uric acid and allows for the more highly soluble xanthine and hypoxanthine to be excreted from the body. (D) It stimulates the purine salvage pathway, thus eliminating the need for production of uric acid. (E) None of the above.

73. In anaerobic circumstances, the re-oxidation ofNADH generated during glycolysis occurs through the following reaction: (A) fructose 1,6-bisphosphate → glyceraldehyde-3P + dihydroxyacetone-P (B) glyceraldehyde-3P → 1,3-DPG (C) pyruvate → lactate (D) dihydroxyacetone-P → glyceraldehyde-3P (E) malate → oxaloacetate

74. Asians and Native Americans may experience flushing and discomfort after consuming a small amount of ethanol in alcoholic beverages. This reaction is attributed to genetic variation in an enzyme responsible for metabolizing the liver metabolite of alcohol. What is this motabolite? (A) methanol (B)acetone (C) glycerol (D) acetaldehyde (E) pyruvate

75. Match the correct form of tetrahydrofolate with the corresponding reaction for Wiich it acts as a coenzyme. (A) 5,10-methenyl-THF: biosynthesis of purines (B) 5-methyl-THF: dUMP→ dTMP (C) 5,10-methylene-THF: glycine →serine (D) 5,10-mcthenyl-THF: methionine→homocysteine (E) All of the above

76. The percentage saturation of hemoglobin by oxygen is increased when one of the following is increased: (A) concentration of 2,3 bisphosphogiycerate (B) concentration of hydrogen ions (C) concentration of Hb (D) parUal pressure of CO2 (E) partial pressure of O2

77. Which of the following describes the coenzyme involved with thymidylate synthase? (A) 5-mefliyl-THF serves as the methyl donor. (B) 10-methyl-THF serves as the methyl donor. (C) 5,10-methylene-THF serves as both methylene donor and reducing agent. (D) 5,10-methenyl-THF serves as both methylene donor and reducing agent (E) S-adenosylmethionine serves as the methyl donor.

78. Which statement regarding allosteric regulation of enzyme activity is false? (A) Allosteric regulators can either activate or inhibit enzyme function. (B) Binding of allosteric effectors induces a confbimational change in the enzyme. (C) Homotropic allosteric effectors compete with substrate for binding sites. (D) Allosteric enzymes usually consist of multiple subunits. (E) Sigmoidal kinetic plots are indicative of tiw presence of allosteric binding sites.

115年 - 115 國立中山大學_學士後醫學系招生考試試題：普通生物及生化概論#138369

115年 - 115 學士後醫學系招生考試試題：普通生物及生化概論#138357

115年 - 115 國立清華大學_學士後醫學系單獨招生試題：生物與生化#138208

115年 - 115 國立中興大學_學士後醫學系公費生招生考試：普通生物及生化概論#138023

114年 - 114 學士後醫學系招生考試試題：普通生物及生化概論#126681

114年 - 114 國立中興大學_學士後醫學系公費招生考試：普通生物及生化概論#126435

114年 - 114 國立中山大學_學士後醫學系招生考試試題：普通生物及生化概論#126236

114年 - 114 國立清華大學_學士後醫學系考試︰生物生化#126232

113年 - 113 國立中興大學_學士後醫學系公費招生考試：普通生物及生化概論#119946

113年 - 113 國立清華大學_學士後醫學系招生考試_學士後醫學系：生物及生化#119851