76. Which of the followings describes the initial bond formation in the covalent intermediate in the reaction catalyzed by chymotrypsin?
(A) Serine 195 and the carbonyl carbon in the peptide backbone
(B) Serine 195 and the nitrogen in the peptide backbone
(C) Histidine 57 and the carbonyl carbon in the peptide backbone
(D) Histidine 57 and the nitrogen in the peptide backbone
(E) Aspartate 102 and the carbonyl carbon in the peptide backbone

72. The pentose phosphate pathway of glucose oxidation produces ______. (A) coenzyme Q10 (B) FADH2 (C) glucose-1-phosphate (D) NADH (E) ribose-5-phosphate

73. The thickness of endoplasmic reticulum membrane is about 37.5 Å. Which one of the followings is closest to this length? (A) alpha-helix with 10 amino acid residues long (B) alpha-helix with 40 amino acid residues long (C) alpha-helix with 80 amino acid residues long (D) B-DNA with 10 base pairs long (E) B-DNA with 40 base pairs long

74. There are cholesterols and cholesterol esters in LDL. How and where are cholesterol esters generated in a human body? (A) Cholesterol esters are generated by lecithin: cholesterol acyltransferase in endothelial cells. (B) Cholesterol esters are produced by lecithin: cholesterol acyltransferase in macrophages. (C) Cholesterol esters come from the reaction between free short-chain fatty acids and cholesterols. (D) Cholesterol esters are generated from the reaction between free long-chain fatty acids and cholesterols. (E) Cholesterol esters are produced by lecithin: cholesterol acyltransferase in the bloodstream.

75. Okazaki fragments are ______. (A) short DNA pieces that explain how DNA is synthesized on the lagging strand (B) short DNA pieces that explain how DNA is synthesized on the leading strand (C) the remnants of the original strands that are dispersed in the new double stranded DNA molecules (D) RNA primers used for DNA replication (E) Fragments of mRNA that are processed into mature mRNA molecules

77. Which of the following statements about farnesyl-linked proteins and glycosylphosphatidylinositol (GPI)-linked proteins is TRUE? (A) Farnesyl-linked proteins and GPI-linked proteins are randomly distributed in the plasma membrane. (B) Farnesyl-linked proteins and GPI-linked proteins are frequently associated with the outer leaflet of the plasma membrane. (C) Farnesyl-linked proteins and GPI-linked proteins are frequently associated with the inner leaflet of the plasma membrane. (D) Farnesyl-linked proteins are associated with the outer leaflet of the plasma membrane, and GPI-linked proteins are frequently associated with the inner leaflet of the plasma membrane. (E) Farnesyl-linked proteins are associated with the inner leaflet of the plasma membrane, and GPI-linked proteins are frequently associated with the outer leaflet of the plasma membrane.

78. What is an important component(s) to transport ammonia from skeletal muscles and the other tissues to the liver? (A) Albumins (B) Alanine from skeletal muscles and glutamine from most tissues (C) Glutamates (D) Alanine from skeletal muscles and glutamate from most tissues (E) Glycine from skeletal muscles and glutamate from most tissues

79. Which statement about energy metabolism in patients with type I diabetes mellitus and poor blood glucose control is NOT true? (A) Ketone bodies are mainly derived from the metabolism of glucose-produced acetyl-CoA. (B) Ketone bodies can replace glucose as a cellular energy source. (C) Intermediate products of the Krebs cycle, such as oxaloacetate, are used in gluconeogenesis, leading to an increase in blood glucose. (D) Due to the lack of oxaloacetate, acetyl-CoA cannot enter the Krebs cycle, resulting in its conversion into ketone bodies. (E) Fatty acids are converted into ketone bodies as an alternative energy source in the absence of glucose.

80. A young boy is unusually tall and presents with joint laxity and retinal detachment. Examination reveals a mutation in the tripeptide repeat of type II collagen, affecting its quaternary structure. Which amino acid is most likely affected by this mutation? (A) hydroxylysine (B) hydroxyproline (C) glycine (D) tryptophan (E) proline

複選題81. How is DNA recombination achieved during meiosis? (A) Double-strand break recombination (B) Single-strand break recombination (C) Telomere recombination (D) Centromere recombination (E) Homologous recombination

82. What is the main pharmacological action of benzoate and phenylbutyrate, which are used to treat urea cycle disorders? (A) It provides intermediates required for the urea cycle to enhance the efficiency of the entire urea cycle. (B) It acts as allosteric activators of carbamoyl phosphate synthase I to enhance the efficiency of the urea cycle. (C) Their metabolites combine with glycine and glutamine, respectively, to form derivatives that are excreted, reducing the burden on the urea cycle. (D) It promotes the synthesis of arginine to prevent arginine deficiency. (E) It increases the activity of ornithine transcarbamylase to facilitate urea synthesis.