87. Protein three-dimensional structures can NOT be determined by_________.
(A) X-ray crystallography
(B)NMR
(C) cryo-electron microscopy
(D) high performance liquid chromatograpby
(E) small angle X-ray scattering

83. What is the major purpose of the pentose phosphate pathway? (A) Generate NAD' for oxidative biosynthesis (B) Generate NADH for reductive biosynthesis (C) Generate FADH2 for reductive biosynthesis (D) Generate ribose-5-phosphate for nucleotide biosynthesis (E) Generate ATP for energy biosynthesis 

84. Within the electron transport chain, complex _________ represents the entry point for electrons from NADH while complex__________ represents the entry point for electrons from FADH2. (A) Ⅰ；Ⅱ (B) II；III (C) III；IV (D) Ⅰ； III (E) II； IV

85. People who can have relatively high level of pyruvate in their blood due to_________；what enzyme that contains this cofactor is inactivated?_________ (A) Vitamin B deficiency: pyruvate carboxylase (B) Vitamin C deficiency: pyruvate kinase (C) Thiamine deficiency: pyruvate dehydrogenase (D) Alcohol intake； pyruvate dehydrogenase (E) PLP deficiency: pyruvate transaminase

86. What cofactors are in acyl-CoA dehydrogenase? (A) FAD (B) ATP (C) Mg2+ (D) NADH (E)cAMP

88. Intrinsic fluorescence of GFP is contributed by________. (A) cyclization and oxidation of residues: Ser - Trp - Gly (B) cyclization and oxidation of residues: Ser - Tyr - Gly (C) cyclization and oxidation of residues: Ser - Tyr - Ala (D) cyclization and oxidation of residues: Thr - Tyr-Gly (E) cyclization and oxidation of residues: Gly - Trp - Ser

89. Several classes of hydrolases are localized in_________. (A) Golgi vesicle (B) lysosomes (C) late endosome (D) mitochondria (E) nucleus

90. Match the co-enzyme in List I severing as the transient carrier with the specific item or functional group in List II:(A) A -III, B -I, C-II,D-V,E-IV (B) A - IV, B -I, C - II.,D - V,E -II (C) A -I, B -II, C-III, D -IV,E-V (D) A - II, B - V, C-III, D -IV,E -1 (E) A - 1, B - V, C-III, D -IV,E-II

1. What is the maximum absorption wavelength of DNA? (A) ~200 nm. (B) ~220 nm. (C) ~240 nm. (D) ~260 nm. (E) ~280 nm.

2. Thymine in DNA is replaced by uracil in RNA. What is the structural difference between thymine and uracil? (A) Thymine has one methy! group in its structure whereas uracil does not. (B) Thymine has one primary amine group in its structure whereas uracil does not. (C) Uracil has one methy! group in its structure whereas thymine does not. (D) Uracil has one primary amine group in its structure whereas thymine does not. (E) Uracil has a two-ringed structure, whereas thymine has a single-ringed structure.

3. Which of the following statements is the correct regarding genome structure? (A) All the chromosomes in prokaryotic cells are circular. (B) Every prokaryotic cell contains only one chromosome. (C) Genome size is the total number of base pairs in one copy of a haploid genome. (D) An organism's complexity is directly proportional to its genome size. (E) The protein-coding genes comprise ~1.5% of the Escherichia coli genome.