複選題

24. Proteins may non-covalently interact with small molecules such as GTP, , etc. Which of the following statement is/are NOT correct?
(A) after first oxygen binding, hemoglobulin adapts a new conformation and could interact the second oxygen molecule better
(B) neurotransmitter glutamate triggers calcium influx by non-covalently binding to calcium channel on the post-synaptic membrane.
(C) facilitates the hemophilic interaction between E-cadherin
(D) binding to either GTP or GDP activates small G protein, such as Ras.
(E) when cellular ATP level is high, excessive ATP non-covalently binds to and inhibits pyruvate kinase, which mediates glycolysis and ATP production

複選題20. GAL4 is a transcription activator in yeast which promotes expression of a group of genes. In the upstream of genes driven by GAL4, there are one or more copies of a related 17-bp sequence known as To show that UASGAL is the GAL4 responsive element, one constructed a lacZ reporter as shown in (a) and showed that the expression of lacZ is activated in galactose media in wild-type cells but not in gal4 mutants. She also did another set of experiments, in which various mutant GAL4 molecules are are examined for their transcription activator activities. Which of the following conclusions can be drawn from her experiments? (A) N terminal aal-74 is required for GAL4 binding to UAS sequence (B) N terminal aal-74 is sufficient to bind to UAS sequence (C) C terminal aa738-881 is required for GAL4 to activate lacZ expression (D) the fusion protein composed of aal-74 and aa738-881 is sufficient to activate lacZ expression. (E) aa75-737 is not dispensable for lacZ expression

21. Cellular proteins give cells structure and perform many cellular tasks except for (A) RNA-dependent RNA polymerase (B) cytoskeleton of cells (C) ion channels (D) ribozymes (E) kinases

複選題22. Which of the following statement are correct (A) DNA severs as a template for DNA synthesis (B) RNA severs as a template for protein synthesis (C) DNA serves as a template for miRNA synthesis (D) DNA serves as a template for mRNA synthesis (E) protein serves as a template for RNA synthesis

複選題23. The fluidity of lipid membranes in cells on depends on (A) temperature (B) the amount of unsaturated fatty acyl chain (C) the length of the fatty acid chain (D) the amount of cholesterol (E) the surface area of lipid membranes

複選題25. Proteins could be covalently modified by chemicals and small peptides, such as (A) phosphorus (B) ubiquitin (C) methyl group (D) acetyl group (E) Sumo

26. If you receive from your collaborator a DNA plasmid with a map shown below. Which of the following methods could help you to check if you have received a right plasmid?(A) Run the un-cut supercoiled form plasmid DNA in an agarose gel with DNA size marker. You find that the supercoiled plasmid migrates to the position between 5kb and 6 kb bands. (B) You digest the plasmid DNA with BgIII and run the cut plasmid DNA in an agarose gel with DNA size marker. You find that the cut plasmid migrates to the position between 5kb and 6 kb bands. (C) You digest the plasmid DNA with EcoRI and run the cut plasmid DNA in an agarose gel with DNA size marker. You find that the cut plasmid migrates to the position between 5kb and 6 kb bands. (D) You digest the plasmid DNA with BgIII and EcoRI. Then you run the cut plasmid DNA in an agarose gel with DNA size marker. You find 4.5kb and 738bp bands after double digestion. (E) Sequence the plasmid using a primer specific to mRFP.

複選題27. BrdU is an analog of thymine that can be incorporated into double stranded DNA during  DNA  polymerization in S phase. Unsynchronized cells at various stages of cell cycle are first treate for 2 hours and then cultured in the absence of BrdU for another 4 hours. What would happen to those unsynchronized cells exposure to BrdU?(A) BrdU is incorporated into all the unsynchronized cells. (B) If a cell is labeled by BrdU, only one of the sister chromatins is labeled (C) If a cell is labeled by BrdU, only one strand of DNA is labeled (D) In the 2-hour BrdU pulse, only mitotic cells are labeled (E) In the 2-hour BrdU pulse, only mitotic cells are not labeled

28. The following diagram shows a family pedigree of a disease characterized by muscle weakness from (A) autosomal dominant (B) autosomal recessive (C) sex-linked dominant (D) sex-linked recessive (E) mitochondrial inheritance

29. DNA recombination refers to moving a DNA segment from one to another DNA molecule. This process (A) biogenesis of miRNA (B) linkage mapping human mutations that cause diseases (C) gene targeting, replacing a gene by a mutant allele. (D) tissue specific inactivation of a target gene by the Cre/loxP system. (E) to repair a DNA double strand break

30. Which of the following descriptions about exon, intron, 5' UTR, and 3' UTR is/are NOT correct (A) nonsynonymous mutation is a nucleotide change in exon that changes amino acid sequence of the encoded protein. (B) synonymous mutation is a single nucleotide change in intron that would never cause any change in the amino acid sequence of the encoded protein. (C) although not translated, the nucleotide sequence in the 5' UTR of mRNA corresponds to genomic sequence of exons but not introns. (D) although not translated, mutation in 3' UTR could profoundly affect mRNA stability. (E) mutation in intron sometimes affects protein sequence by introducing mRNA splicing errors.