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Key for Exam 3 • Biology II • Winter 2013 Multiple Choice Questions

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Key for Exam 3 • Biology II • Winter 2013 Multiple Choice Questions Key for Exam 3 • Biology II • Winter 2013 Multiple Choice Questions. Circle the one best answer for each question. (1 point each) 1. Which of the following is not part of the cell theory: A. All cells come from other cells. B. Only eukaryotic cells have membrane-bounded organelles. C. The cell is the smallest living unit of a living thing. D. All living things are made up of cells. 2. A protein that belongs in the plasma membrane of a eukaryotic cell might be found (at some point) in which organelle: A. Golgi apparatus B. ribosome C. cytoplasmic reticulum D. nucleus E. mitochondrion 3. A phospholipid is composed of: A. three fatty acids and a molecule of glycerol B. chains of hydrophobic amino acids C. two fatty acids, a molecule of glycerol and a highly hydrophilic group D. amphipathic fatty acids E. a phosphate, a ribose or deoxyribose sugar, and a fatty acid 4. A membrane would be more permeable if: A. …its phospholipids had longer tails. B. …its phospholipids had shorter tails. C. …it contained more cholesterol. D. …its phospholipids had more saturated tails. E. …its proteins were more hydrophobic. 5. An enzyme is working at its Vmax: A. …at the high point of the product vs. time curve. B. …when its active site is continuously full of substrate. C. …when the concentration of substrate is equal to its km. D. …when it is assayed at its optimum temperature and pH. E. …at the early time points when its slope is the steepest. 6. In an enzyme-catalyzed reaction, the role of the enzyme is to: A. …increase the available activation energy. B. …make an endergonic reaction exergonic. C. …make an exergonic reaction endergonic. D. …use ATP energy to run a thermodynamically unfavorable reaction. E. …speed up the rate of the reaction. Version A p. 1 of 12 12 March 2013 7. Choose the correct citation format for the reference listed below. Sastri, J., C. O’Connor, C. M. Danielson, M. McRaven, P. Perez, F. Diaz-Griffero, and E. M. Campbell. 2010. Identification of residues within the L2 region of rhesus TRIM5α that are required for retroviral restriction and cytoplasmic body localization. Virol. 405:259-266. A. Campbell, et al., 2010 B. Sastri, et al., 2010 C. Sastri, J., et al., 2010 D. Sastri and Campbell, 2010 E. O’Connor, et al., 2010 8. Which of the following is not true about a recessive genetic trait? A. Only homozygous recessive individuals show the trait. B. One allele must be inherited from each parent in order to show the trait. C. The allele responsible for the trait is usually rare. D. The allele responsible for the trait usually encodes a non-functional protein. E. It is possible to have the allele associated with the trait but not show the trait. 9. A possible genetic symbol for an allele that produces red pigment and shows incomplete dominance would be: A. CRCW B. AQ C. R D. a filled circle or square E. Cr 10. The number of alleles of one gene that can be found in one individual is: A. 2 B. 1 C. 1 or 2 D. 3 E. limited only by the number of nucleotides that might be mutated 11. Whose experiment provided evidence that the genetic material of a virus is composed of DNA? A. Griffiths B. Avery, McCarty and MacLeod C. Hershey and Chase D. Watson and Crick E. Meselson and Stahl 12. Which of the following can add nucleotides to a 5′ end during replication? A. primase B. DNA polymerase I C. DNA polymerase III D. RNA polymerase II E. none of the above Version A p. 2 of 12 12 March 2013 13. A mutation converts a T nucleotide within a coding sequence to an A. This mutation is a: A. …missense mutation. B. …nonsense mutation. C. …frameshift mutation. D. …silent mutation. E. …there is not enough information to decide. 14. Meiosis I separates: A. …homologous pairs of chromosomes. B. …sister chromatids. C. …the X chromosome from the Y chromosome. D. …gametes from somatic cells. E. …the two strands of a DNA molecule. 15. A sex-linked gene is located: A. …on the same chromosome as another gene. B. …on the Y chromosome. C. …on the X chromosome. D. …on the X or Y chromosome. E. …in the gamete cells. 16. When an E. coli cell is growing in broth containing glucose and lactose: A. …the lac repressor and the CAP protein are both bound to DNA. B. …the CAP protein is bound to DNA, but not the lac repressor. C. …cAMP is bound to the CAP protein. D. …lactose is bound to the lac repressor. E. both A and D. 17. The light reactions of photosynthesis produce: A. …glucose. B. …ATP and NADPH. C. …ATP and NADP+. D. …three-carbon carbohydrates. E. …water. 18. We know that a molecule is being oxidized at a particular step in a biochemical pathway when: A. …a molecule of ATP is produced. B. …a molecule of NAD+ is produced. C. …a molecule of FADH2 is produced. D. …a molecule of pyruvate is produced. E. …a proton is pumped out by the electron transport system. Version A p. 3 of 12 12 March 2013 19. When a yeast cell ferments pyruvate to form ethanol and CO2, what important purpose does this step serve? A. increases the amount of ATP that can be produced from glucose B. produces the alcohol used for energy generation by yeast cells C. produces oxidized forms of electron carriers D. produces ethanol that can be further broken down in the citric acid cycle E. prevents buildup of toxic pyruvate 20. Adrenaline is a peptide hormone. We would expect to find its receptor: A. inserted into the cell membrane of target cells B. in the cytoplasm of target cells C. in the nucleus of target cells D. in the cytoplasm of both target and non-target cells E. bound to the DNA of target cells 21. BLAST is a program that can: A. …determine the DNA sequence of a gene whose function is unknown. B. …identify diseases that may be associated with a gene whose function is unknown. C. …find genes in a database with sequences similar to that of a gene whose function is unknown. D. …determine the biochemical function of a gene whose function is unknown. E. …waste the time of students in an introductory biology course. 22. Which of the following enzymes would not be used in cloning a gene by one of the methods described in class? A. a DNA polymerase B. an RNA polymerase C. reverse transcriptase D. DNA ligase E. a restriction endonuclease 23. In order to express a human gene in a bacterial cell, we would have to provide: A. a Shine-Dalgarno sequence B. a TATA box C. introns D. a 5′ cap E. human ribosomes 24. A yeast spore consists of: A. …two diploid cells in the process of mitosis (budding). B. …four diploid cells surrounded by an ascus. C. …one resistant cell surrounded by a protective coat. D. …several yeast cells gathered together for protection. E. …four haploid cells surrounded by an ascus. Version A p. 4 of 12 12 March 2013 25. Calculating the standard deviations for two sets of measurements can tell you: A. …how close they are to the actual values. B. …whether there is a significant difference between the two sets of data. C. …whether your hypothesis is supported by the data. D. …how accurate your measurements were. E. …whether the average measurement is valid or not. 26. When you assayed tyrosinase in potato extracts, you were directly measuring: A. …absorbance of tyrosinase. B. …activity of tyrosinase. C. …concentration of tyrosinase. D. …production of a quinone. E. …absorbance of pyrocatechol. 27. When you performed the Ames test on the chemical you wanted to screen as a possible carcinogen, the positive control was: A. …the number of colonies on minimal medium plates in the absence of the chemical. B. …the number of colonies formed on LB plates. C. …the number of colonies on minimal medium plates for cells treated with sodium azide. D. …the number of colonies on minimal medium plates when you used the highest concentration. E. …the number of cells originally present in each spot on the minimal medium plates. 28. In gel electrophoresis, DNA moves toward: A. …the positive electrode. B. …the negative electrode. C. …the smallest fragments. D. …the DNA ladder. E. …the dark blue tracking dye. Version A p. 5 of 12 12 March 2013 29. How does each factor below participate in the process of gene expression? Circle all of the choices that are correct. (1 point for each factor) a. Promoter Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation b. -10 and -35 Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation c. Ribosome Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation d. Stop codon Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation e. Operator Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation f. trp Repressor Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation g. CAP Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation h. Estrogen receptor Organism: Eukarote Prokaryote Composed of: DNA RNA Protein Process: Transcription Translation Version A p. 6 of 12 12 March 2013 Short Answer Questions. Please be sure to read the questions carefully and be sure you have answered what is being asked. Think before you write! The best answers are brief and to the point.
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