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

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

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

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. 

5. Which of the following DNA polymerases removes primers in Escherichia coli? (A) DNA polymerase I. (B) DNA polymerase II. (C) DNA polymerase III. (D) DNA polymerase IV. (E) DNA polymerase V.

6. Which of the following statements is correct regarding the replication folk? (A) Topoisomerase acts to separate two strands of duplex DNA. (B) Synthesis of the two strands of DNA is not simultaneous. (C) The lagging strand is the strand on which the polymerase moves in the same direction as the movement of the replication fork. (D) The DNA fragment formed on the lagging strand is called the Okazaki fragment. (E) Primase acts to join breaks in the phosphodiester backbone of DNA.

7.Telomerase: (A) solves the end replication problem of leading-strand synthesis. (B) uses endogenous DNA as template. (C) acts to extend the 3' end of the telomere. (D) synthesizes double-stranded DNA. (E) is present in all the eukaryotes.

8.Direct uptake of exogenous naked DNA through the cell membrane is called: (A) conjugation. (B) injection. (C) infection. (D) transformation. (E) transduction.