2. Which one of the following statements about the structure of RNA is NOT true?
(A) RNA is capable of forming secondary structure.
(B) RNA is capable of forming tertiary structure.
(C) RNA is capable of forming pseudoknots.
(D) RNA is capable of forming B-sheets.

28. Which of the following methods concerning absorption are INCORRECT? (A) UV-Visible spectroscopy of organic compounds is usually associated with n → π*and π → π*(B) The intensity of absorbance is proportional to the log of the absorbing species concentration (C) An atomic absorption spectrum consists of a series of line peaks (D) X-ray absorption spectroscopy (XAS) can probe the chemical surroundings around an atom of interest.

29. Which of the following statements concerning fluorescence are INCORRECT? (A) The lifetime of fluorescence is s. (B) The difference between the excitation and emission wavelengths is called the Stokes Shift. (C) Fluorescence intensity is sensitive to environmental factors, such as pH and solvent polarity. (D) The fluorescent quantum yield is dependent of excitation intensity.

30. Which of the following statements concerning gravimetric methods are INCORRECT? (A) The particle size of a precipitate can be enhanced by minimizing the relative super-saturation during precipitate formation (B) An electric double layer consists of the primary adsorption layer and counter-ion layer. (C) Peptization is a process in which a precipitate is beated in the mother liquor. (D) A gravimetric volatilization method is the classical method for the determination of hydrogen and carbon in organic compounds

1. DNA-binding proteins primarily recognize a specific sequence of double-stranded DNA through_________. (A) interactions with the exposed chemical groups in the DNA sugar-phosphate backbone (B) interactions with the exposed chemical groups in the minor groove of the DNA (C) interactions with the exposed chemical groups in the major groove of the DNA (D) attraction between the protein and negative charges on DNA

3. Consider an experiment in which nucleic acids are separated using agarose gel electrophoresis. In the gel you load the following samples: Lane 1: a population of linearized 3000-bp double-stranded DNA (dsDNA) molecules. Lane 2: a population of circular 3000-bp double-stranded DNA (dsDNA) molecules Which population of nucleic acids would most likely migrate through the gel fastest, and in which direction through the gel will these molecules migrate? (A) The linearized dsDNA would most likely migrate faster than the circular dsDNA. AlI DNA molecules would migrate toward the positive end of the gel. (B) The linearized dsDNA would most likely migrate faster than the circular dsDNA. AIl DNA molecules would migrate towards the negative end of the gel. (C) The circular dsDNA would most likely migrate faster than the linearized dsDNA. All DNA molecules would migrate toward the positive end of the gel. (D) The circular dsDNA would most likely migrate faster than the linearized dsDNA. All DNA molecules would migrate toward the negative end of the gel

4. Which of the following bioinformatics analyses involves scanning sequences in the genomes of related organisms to identify conserved non-coding regions, which may represent unknown regulatory elements? (A) BLAST (B) VISTA (C) genome annotation (D) genome editing

5. In a linear eukaryotic chromatin sample, which of the following strands is looped into domains by scaffolding? (A) the 30-nm chromatin fiber (B) the metaphase chromosome (C) DNA with H1 only (D) the 10-nm chromatin fiber

複選題6. Which of the following statements is true about histones? (A) The mass of histone in chromatin is approximately nine times the mass of DNA. (B) The carboxyl end of each histone extends outward from the nucleosome and is called a "histone tail." (C) Histones are found in mammals, but not in other animals or in plants or fungi. (D) Histone H1 is not present in the nucleosome bead； instead, it draws the nucleosomes together.

7. Why do histones bind tightly to DNA? (A) Histones are highly hydrophobic, and DNA is hydrophilic. (B) Both histones and DNA are strongly hydrophobic. (C) Histones are covalently linked to the DNA. (D) Histones are positively charged, and DNA is negatively charged.

8. Why might they be conducting such an experiment? (A) to find the location of this gene in the human genome (B) to collect population data that can be used to assess natural selection (C) to collect population data that can be used to study genetic drift (D) to find which of the students has which alleles