Final Exam, BIO201B, 2002 1(A) white evenName___________________________There is only one right answer for each question.1. The purpose of the nucleosome is:A. Help organize and compact eukaryotic heterochromatin and eukromatinB. To organize prokaryotic DNA to keep it togetherC. To pull together non-histone proteins into a core complexD. To unwind heterochromatin to make it transcriptionally activeE. To provide a place for ribosomal subunit assembly2. In a redox couple where electrons are passed from compound B to compound A, this electron transfer can only happen if:A. B has a higher reduction potential than AB. The Gibb’s free energy of B (GB) is lower than GAC. B has a lower Eo value than AD. A is a better reducing agent than BE. B is more oxidized than A3. Which of the following is most likely to bind to the cytoplasmic side of the nuclear pore complex?A. NLS-importin complex B. RibosomesC. ExportinD. SRPE. Nuclear lamina4. Kinetochore proteins associate primarily with:A. CentromeresB. CentrosomesC. CentriolesD. CentrifugesE. Central pairs5. If a nascent protein on a eukaryotic polysome contains a signal sequence but no stop-transfer sequence, the mature protein would most likely be:A. A soluble protein in the cytoplasmB. A membrane bound protein in the RER (rough endoplasmic reticulum)C. A soluble protein inside the RER (in the lumen of the RER)D. A soluble protein inside the nucleusE. Longer than other proteins which don’t have stop-transfer sequences6. The main goal of the pulse-chase experiments involving radioactive amino acids and autoradiography of cells at different times (as described in BIO201B) was to:A. Prove that translation occurs on polysomesB. Show that there is no protein synthesis inside of the nucleusC. Identify where the nucleolus isD. Follow the path of a newly synthesized protein through the endomembrane systemE. Determine where proteins are glycosylated17. A free polysome can be directed to bind to the RER by:A. GTP B. A signal sequence on a nascent peptideC. ImportinD. A chaperoneE. The mature protein8. Complex carbohydrates for glycoproteins can be assembled in all of the following except:A. RER lumenB. CytoplasmC. Cis-golgi lumenD. Lysosome lumenE. Trans-golgi lumen9. Mitosis involves:A. Metaphase and cytokinesisB. Interphase and M-phaseC. Cell divisionD. Pachytene and leptoteneE. Nuclear division but not cell division10. The main goal of the Meselson-Stahl experiments with 14N DNA and 15N DNA was:A. To determine whether newly synthesized DNA contains nitrogenB. To see whether 15N makes DNA heavierC. To see if the banding patterns of DNA from bacteria grown on 14N for two generations was consistent with semi-conservative replicationD. To determine which is better for labeling eukaryotic DNA, 15N or BrdU.E. To show that bacterial DNA is double stranded11. An experiment described in BIO201B lecture involved radioactive thymidine (3H thymidine) pulse-chase labeling of cells for the purpose of determining the length of S-phase. When the datawas plotted as a figure, the information on the y-axis was:A. Time (in hours) after addition of radioactive thymidineB. Percent of all cells which are radioactiveC. Amount of DNAD. Percent of cells in mitosis which are radioactiveE. Percent of cells in S-phase12. Disperse (not compacted), eukaryotic DNA is seen in:A. TetradsB. ZygoteneC. Mitotic anaphaseD. All of interphaseE. G1 but not in G213. Which of the following most accurately describes the labeling of macromolecules in each of the phases listed (for human cells)? BrdU 3 H thymidine Radioactive amino acids 3 H uracilA. Mitosis yes no no noB. Meiosis I no yes no noC. S-phase yes yes no noD. G1yes no yes yesE. Meiosis II yes yes no no214. Which human cell cycle phase is most likely represented in the picture below?A. ProphaseB. MetaphaseC. AnaphaseD. Telophase E. Prometaphase15. A difference between human mitotic prophase and mitotic anaphase A is:A. There are no visible centrosomes in prophase but there is in anaphase AB. Chromatin is compacted in prophase but not in anaphase AC. Synaptonemal complexes are seen in mitotic prophase but not in anaphase AD. Spindle microtubules are not connected to kinetochores in prophase but they are in anaphase AE. Dynein moves mitotic chromosomes (paired chromatids) towards the middle of the spindle in prophase but only kinesin is needed to pull them apart in anaphase A16. Which of the following is true?A. The H+ gradient across the lysosomal membrane is commonly used to make ATP in the cytoplasmB. Clathrin helps to pinch off membranes to form vesicles from both the plasma membrane and trans golgi network (TGN)C. Soluble cargo inside the endomembrane system does not bind to receptors until they reach the TGND. Soluble proteins destined to remain inside the RER are targeted to stay there by mannose-6-phosphate receptorsE. There is only one kind of v-SNARE but many kinds of t-SNAREs.17. Which of the following best describes human mitotic metaphase?# of pieces of dispersed # of amount # of chromatin chromatids ploidy of DNA centriolesA. 92 92 1n 1x 2B. 92 46 2n 2x 2C. 46 0 2n 2x 2D. 0 46 2n 4x 4E. 0 92 2n 4x 418. The purpose of meiosis in humans is:A. To produce cells (gametes) with the same ploidy and DNA amount as the parentsB. Reduction division to prepare gametes for fertilizationC. Diploidization of gametesD. To keep maternal and paternal genes together to prevent independent assortmentE. To assure cell division and fertilization without genetic recombination19. One way to tell if a human cell is in meiosis or mitosis is:A. There is always twice as much DNA in mitotic cells compared to meiotic cellsB. There is no telophase in meiosis but there is in mitosisC. Cells are always diploid in mitosis but all meiotic cells are haploidD. There is a reduction in the amount of DNA during mitosis but not in meiosis E. Sister chromatids can be syntelic in meiosis but not in mitosis320. A main difference between gamete production in male and female humans is:A. The leptotene and zygotene phases are much longer during sperm