Download Exam 3

MCB 302
Fall, 2011
Exam 3
Name:_________________________________
Panther ID:_____________________________
Multiple Choice Questions: mark your best choice answer letter on the Scantron Answer Sheet.
1. A bacterial phylum is a group of organisms that share a common ancestor that diverged early from other bacteria
based on:
a. 16s RNA sequences. b. the presence of certain plasmids. c. their genomic size. d. having 70S or 80S ribosomes.
e. the presence of a cell wall.
2. Which of following is not involved in initiation of spore formation in Firmicutes?
a. carbon starvation. b. light limitation. c. phosphate starvation. d. nitrogen starvation.
e. lowpH.
3. Bacillus ________________ produces a biological insecticidal toxin.
a. subtilis. b. anthrasis. c. thuringiensis. d. thermophilus. e. halodurans.
4. What of the following is correct about lactic acid bacteria:
a. Aerotolerant obligate fermenters. b. They are non-spore forming bacteria.
phosphorylation to produce ATP. d. all of the above. e. none of the above.
c. They use substrate level
5. Telomeres are found in the:
a. rickettsias and mitochondria. b. cyanobacteria and chloroplasts. c. Streptomyces. d. Planctomycetes.
e. Dienococcus-Thermus group.
6. The cell wall of Mycobacterium tuberculosis contains:
a. arabinogalactan. b. mycolic acids. c. phenolic glycolipids. d. all of the above.
e. none of the above.
7. The gamma proteobacteria contain a genus that can oxidize H2S to So; it is:
a. Escherichia. b. Chromatium. c. Shigella. d. Proteus. e. Rhodomicrobium.
8. The following bacterial genera belong to the Enterobacteriaceae. In particular ______________ display swarming
behavior prior to forming ____________.
a. Escherichia; colonies. b. Proteus; biofilms. c. Pseudomonas; endospores. d. all of the above. e. none of them.
9. Bdellovibrio species have the ability to:
a. form endospores. b. form filaments. c. parasitize Gram negative bacteria. d. oxidize iron.
e. photosynthesize.
10. The causative agent of syphilis is:
a. Holandina. b. Leptospira. c. Spirocheta.
d. Treponema
.e. Cristispira.
11. Branched chains can increase membrane stability, they are:
a. isoprenoids. b. ester linked. c. phospholipids. d. fatty acids.
e. none of these.
12. The energy yielding process of __________________ occurs only in the archaea.
a. fermentation. b. sulfur oxidation. c. hydrogen oxidation. d. methanogenesis.
e. anaerobic respiration.
13. Which archaea has/have retinal associated, light driven membrane pumps for H+?
a. allarchaea. b. hyperthermophilicCrenarchaeota. c. Methanobacteriales. d. Haloarachaea.
14. Laboratory isolation of Nanoarchaeumequitans requires the presence of:
a. Sulfolobus. b. Ignicoccus. c. Halobacterium. d. Methanococcus. e. Thermoplasma.
e. methanogens.
15. An organism found on human skin that derives benefit from the host but does not harm the host is a:
a. parasite. b. commensal. c. opportunist. d. pathogen. e. mutualist.
16. Which of the following is not an integral part of the inflammatory response?
a. dilation of blood vessels. b. histamines. c. prostaglandins. d. extravasation.
e. antibody synthesis.
17. Microbial colonization of the eye is inhibited by the presence of:
a. interferons. b. complement. c. mucous. d. defensins. e. lysozyme.
18. The mucociliary escalator functions to:
a. trap and sweep pathogens into urine. b. kill via complement activity. c. harbor a normal flora.
d. produce fatty acids and a low pH. e. trap and sweep microbes up and ultimately into the stomach.
19. Which part of the genitourinary tract maintains a normal flora?
a. kidney. b. ureters. c. bladder. d. urethra. e. vagina.
20. The major phagocytic cells in the body are:
a. T and B lymphocytes. b. basophils and eosinophils.
c. erythrocytes.
d. neutrophils. e. ciliated epithelial cells.
21. What is the correct order of events in phagocytosis? (1) discharge of waste material. (2) fusion of the phagosome
with a lysosome. (3) adherence of the microbe to a phagocyte. (4) killing and digestion of ingested microbe. (5)
formation of a phagosome. (6) ingestion of the microbe by the phagocyte.
a. 3, 6, 5, 2, 4, 1. b. 3, 4, 6, 5, 2, 1. c. 6, 5, 2, 4, 3, 1. d. 5, 2 3, 6, 4, 1. e. none of these.
22. Which of the following is produced by NK (natural killer) cells to puncture the membrane of target cells.
a. perforins. b. trypsins. c. maganinins. d. lysins. e. defensins.
23. A small segment of an antigen that is capable of eliciting an immune response is called a(n):
a. hapten. b. clonotope. c. aggretope.
d. epitope. e. naïve antigen.
24. Which of the following is most likely to elicit the strongest antigen specific immune response in a human?
a. Plasmodiumfalciparium (causes malaria) outer membrane protein. b. HIV RNA genome.
c. Herpes DNA genome. d. Streptococcusmutans polysaccharide capsule. e. E. coli cell membrane phospholipid.
25. Capping of B-cells receptors on the surface of an antigen exposed B cell causes what to occur?
a. T helper cell proliferation and T regulatory cell differentiation.
b. complement cascade signaling and antigen destruction.
c. cell signaling cascade inducing cell proliferation and differentiation.
d. VDJ gene switching, recombination and hypermutation.
e. neutrophil phagocytosis of the antigen.
26. A mutation that caused a person to have an ineffective complement C6 protien would have a direct effect on the
formation of:
a. complement-antibody complex. b. C3convertase. c. C3b opsonin for phagocytosis.
d. membrane attack complex. e. C5convertase.
27. Inhalation of allergenic pollen in a susceptible person causes:
a. crosslinking of IgE on mast cells. b. immediate anaphylaxis. c. binding to sensitized T cells.
d. increasedcAMP levels. e. immediate leukotriene release.
28. HIV virus takes up residence in what immune cell using which receptors?
a. APC cells; MHC I and II receptors. b. TC cells; CD8 receptors. c. TH cells; CD4 receptor.
e. TH0 cells; TCR receptor.
d. B cells; CD 40 receptor.
29. A liver cell (hepatocyte) infected with a virus will express the viral antigens on:
a. TCR. b. MHC I. c. MHC II. d. CD4. e. CD8.
30. The difference between an antibody allotype and isotype is:
a. isotype is the different in the constant regions: allotype are differences within isotypes.
b. allotype is the different in the constant regions; isotype are differences within allotypes.
c. isotype is the different in the constant regions; allotype are alternations in the variable regions.
d. isotype are alternations in the variable regions; allotype are differences within isotypes.
e. isotype are alternations in the variable region of one person; allotype are alternations in variable regions among
species.
Short Written Answer Questions: Remember that numerical answers without their units are meaningless and get
zero points.
1. The human colon contains about 1011 bacteria/gram in the lumen of the colon.
a. Set up a sampling-dilution pattern that would produce about 100 bacteria/plate. (10 points)
b. The average human has about 1014 bacteria in the colon, how many grams of bacteria are in the human colon? (5
points)
2. Diagram the enzyme reactions which constitute the phagocytic oxygen killing system. (15 points)
questions continued on otherside….
3. DiagramIgA using a line diagram of the polypeptide(s) and be sure to label each polypeptide (not parts of a
polypeptide).
a. As it occurs in blood. (5 points)
b. As it occurs in the mucosa. (5 points)