7. A ribozyme is  _____.
(A) a catalyst that uses RNA as a substrate
(B) an enzyme that synthesizes RNA as part of the transcription process
(C) an enzyme that catalyzes the association between the large and small ribosomal subunits
(D) an RNA with catalytic activity
(E) an important component of RNA transport from nucleus to cytoplasm.

3. Which of the following contradicts the one-gene, one-enzyme hypothesis? (A) Alkaptonuria results when individuals lack a single enzyme involved in the catalysis of homogentisic acid. (B) Sickle-cell anemia results in defective hemoglobin. (C) A mutation in a single gene can result in a defective protein. (D) A single antibody gene can code for different related proteins, depending on the splicing that takes place post-transcriptionally. (E) Human insulin is encoded by one gene and processed after translation into two conjugated polypeptides for its active form.

4. In 1928, English microbiologist Frederic Griffith demonstrated that DNA is the genetic material to determine the virulence of bacteria cells; what observations helped this conclusion? (A) The heat-killed pathogenic bacteria + live non-pathogenic bacteria -＞ pathogenic. (B) The heat-killed non-pathogenic bacteria+ live pathogenic bacteria -＞ pathogenic. (C) The transformation of bacteria was carried by a heat-stable genetic material. (D) The heat-treated bacteria protein is pathogenic (E) Pathogenicity reflects the action of the capsule gene.

5. What is the mechanism of information transfer in eukaryotes? (A) Messenger RNA is transcribed from a single gene and transfers information from the DNA in the nucleus to the cytoplasm, where protein synthesis takes place. (B) Transfer RNA takes information from DNA directly to a ribosome, where protein synthesis takes place. (C) DNA from a single gene is replicated and transferred to the cytoplasm, where it serves as a template for protein synthesis. (D) Proteins transfer information from the nucleus to the ribosome, where protein synthesis takes place. (E) Retrovirus-mediated gene transfer can only occur prenatally during pregnancy

6. Which of the following occurs in prokaryotes but not in eukaryotes? (A) post-transcriptional splicing (B) translation in the absence of a ribosome (C) concurrent transcription and translation (D) gene regulation (E) alanine can be added to polypeptide chain by tRNA with different codons

8. A mutant bacterial cell has a defective aminoacyl-tRNA synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The consequence of this for the cell will be that _____.(A) the positions of phenylalanine in proteins will still encode phenylalanine (B) the cell will compensate for the defect by attaching phenylalanine to tRNAs with lysine-specifying anticodons (C) the cell is not able to synthesize lysine (D) the ribosome will skip a codon every time a UUU is encountered (E) proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU

9. A mutation that inactivates a regulatory gene of a repressible operon in an E. coli cell would result in _____.(A) continuous transcription of the structural gene controlled by that regulator (B) irreversible binding of the repressor to the operator (C) complete inhibition of transcription of the structural gene controlled by that regulator (D) continuous translation of the mRNA because of alteration of its structure (E) defects in cell division

10. The primary difference between enhancers and promoter-proximal elements is that enhancers _____.(A) enhance transcription; promoter-proximal elements inhibit transcription (B) are transcription factors; promoter-proximal elements are DNA sequences (C) are at considerable distances from the promoter; promoter-proximal elements are close to the promoter (D) are DNA sequences; promoter-proximal elements are also DNA sequences (E) are only identified in eukaryotic cells but not in prokaryotic cells.

11. To introduce a particular piece of DNA into a plant, you would most likely be successful with which of the following methods? (A) construction of a recombinant lambda phage carrying the specific DNA. (B) introducing a plasmid into the cell (C) infecting the plant cell with a Ti plasmid (D) transcription and translation (E) electroporation followed by recombination

複選題12. Which of the following status may reflect what we know about how the flu virus moves between species? (A) An animal such as a pig is infected with more than one virus, genetic recombination occurs, the new virus mutates, the virus is passed to a new species such as a bird, and the virus mutates again and can now be transmitted to humans. (B) The flu virus in a pig is mutated and replicated in alternate arrangements so that humans who eat the pig products can be infected. (C) An influenza virus gains new sequences of DNA from another virus, such as a herpesvirus; this enables it to be transmitted to a human host. (D) A farmer is infected by human flu and chicken flu viruses at the same time and the recombinant virus could become highly contagious and virulent for human. (E) There is no avian flu virus can directly infect human.

複選題13. Please select all the correct description about M phase of cell cycle. (A) Cyclin dependent kinase 1 (Cdk1) is the key kinase regulate the progression of M phase. (B) Cellular DNA starts to replicate at M phase. (C) The nuclear envelope starts to break down at prophase. (D) The nuclear envelope starts to reorganize at nuclear port complex at telophase. (E) The nuclear pore complexes are completely disassembled into single molecules before M phase.