Microbiology 2124
Second In-Term Examination
March 31, 1998
Professor Robert V. Miller, Ph. D.

General Instructions: Answer all questions on your test paper in the spaces provided. Only answers entered into the appropriate spaces will be marked. Read all questions carefully. Do not exceed space provided for the answer. Always provided the best right answer.
Answer ColumnQuestions 1-45 are 3 points each
1. Spherical bacteria that remain in pairs are called
a. cocci.
b. diplococci
c. bacilli.
d. streptococci.

2. Bacteria reproduce by a process known as
a. miosis.
b. binary fission.
c. mitosis.
d. spontaneous generation.

3. The time interval required for all cells in a bacterial population to grow and divide is known as the
a. generation time.
b. lag time.
c. log time.
d. division time.

4. Bergey's Manual classifies in section 1 those organisms which contain long axial filaments that extend the length of the cell and are attached to the cellular membrane near each end of the cell. These spiralshaped organisms are know as
a. spirilla.
b. bacilli.
c. spirochetes.
d. sarcinae.

5. Endospores are heat-stable resting forms of all of the bacteria listed below, except
a. Bacillus anthracis.
b. Pseudomonas aeruginosa
c. Clostridium perfringens.
d. Clostridium botulinium.

6. An organism that grows at 5ºC is classified as a(n)
a. mesophile.
b. psychrophile.
c. thermophile.
d. extreme thermophile.

7.In Bergey's Manual the chlamydiae are classified with the
a. viruses.
b. cyanobacteria.
c. spore-forming bacteria.
d. rickettsiae.

8. Mushrooms are classified as
a. Ascomycetes.
b. Deuteromycetes.
c. Basidiomycetes.
d. Zygomycetes.

9. In your laboratory course in mycology, you have isolated a fungus that forms hyphae in which the cytoplasm of the various cells can mix freely and there is no separation of nuclei into "cells." An organism with this characteristic is called
a. septate.
b. yeast-like.
c. photosynthetic.
d. coenocytic.

10. The sexual cycle of some fungi have not been identified. These fungi are classified as
a. Oomycetes (i.e., water molds).
b. Ascomycetes.
c. Deuteromycetes (i.e., fungi imperfecti).
d. Basidiomycetes.

11.Yeasts reproduce mainly by
a. conidia.
b. budding.
c. sporangia.
d. basidia.

12. Members of the Basidiomycetes produce club-like structures called basidia. All of the following are classified in this group, except
a. rusts.
b. mushrooms.
c. slime molds.
d. smuts.

13. The organs of locomotion of members of the class Sporozoa are
a. pseudopodia.
b. flagella.
c. cilia.
d. These organisms are non-motile.

14. A. method for the disinfection of milk that allows it to retain its palatability is
a. ultraviolet light.
b. tyndallization.
c. pasteurization.
d. autoclaving.

15. Low temperature is
a. bacteriocidal.
b. a good method of sterilization.
c. bacteriostatic.
d. as effective as high temperature in coagulating proteins.
16. Pasteurization is effective in killing all microorganisms in the solution treated.
True
False

17. Sterilization is the removal of all
a. pathogenic bacteria.
b. life forms.
c. bacterial growth.
d. Gram+ bacteria.

18. The most common (and most effective) concentration of ethyl alcohol used for disinfection of surfaces such as lab benches is
a. 30 %.
b. 50 %.
c. 70 %.
d. 90 %.

19. An agent that temporarily prevents multiplication of a microorganism without necessarily killing it is called a
a. bactericidal agent.
b. sanitizing agent.
c. sterilizing agent.
d. bacteriostatic agent.

20. A criterion that is more important in the selection of a antiseptic than in the selection of a disinfectant is its
a. ability to kill microorganisms.
b. toxicity to animals and humans.
c. shelf life.
d. corrosiveness to metal instruments.

21. How long would it take to produce 1,024 bacterial cells if you start with one viable cell, all offspring are viable, and all cells have a doubling time of 30 minutes?
a. 90 minutes.
b. 150 minutes.
c. 300 minutes.
d. 450 minutes.

22. Which type(s) of bacteria require oxygen for growth?
a. obligate aerobes.
b. microaerophiles.
c. facultative anaerobes.
d. a. and b.

23. Which of the following is(are) incorrectly typed or written.
a. Es. coli.
b. Escherichia coli.
c. Escherichia coli.
d. a and c.

24. Which organism is able to penetrate and reproduce within prokaryotic cells?
a. Campylobacter.
b. Microcyclus.
c. Bdellovibrio.
d. Spirillum.

25. Which of the following species may produce tumorous growths called crown galls on plants?
a. Rhizobium.
b. Azobacter.
c. Agrobacterium.
d. Legionella.

26. What do Escherichia, Salmonella, and Shigella species have in common?
a. They are Gram +.
b. They are obligate anaerobes.
c. They are members of the Enterobacteriaceae.
d. They produce endospores.

27. How do the Cyanobacteria differ from other phototrophic bacteria?
a. The Cyanobacteria do not photosynthesize; the other phototrophic bacteria are capable of photosynthesis.
b. The Cyanobacteria contain carotenoids; the other phototrophic bacteria do not contain carotenoids.
c. Most Cyanobacteria split water to form oxygen; the anoxygenic phototrophic bacteria do not produce oxygen.
d. a. and b.

28. What differences are seen between Bacillus and Clostridium species?
a. Bacillus species are Gram +; Clostridium species are Gram -.
b. Bacillus species are aerobes; Clostridium species are obligate anaerobes.
c. Clostridium specious form endospores; Bacillus species do not.
d. Clostridium species grow in cluster; Bacillus species grow in tetrad formations.

29. Which of the following are produced as a result of fermentation by the yeast Saccharomyces ?
a. Wine, bread.
b. Yogurt, buttermilk.
c. Cheese.
d. Sauerkraut.

30. Which group of algae are unicellular, lack a cell wall, and closely resemble the protozoans by having a pellicle?
a. Dinoflagellates.
b. Diatoms.
c. Euglena.
d. Green algae.

31. Which of the following produce distinctive cell walls called frustules?
a. Diatoms.
b. Euglena species.
c. Dinoflagellates.
d. Volvox species.

32. Which of the following are unicellular non-photosynthetic, eukaryotic microorganisms?
a. Algae.
b. Protozoans.
c. Bacteria.
d. All of the above.

33. The growth of a population of bacteria is plotted on Cartesian graph paper. The growth curve will be
a. linear.
b. sigmoid.
c. hyperbolic.
d. exponential.

34. The growth of a population of bacteria is plotted on semi-logarithmic graph paper. The growth curve will be
a. linear.
b. sigmoid.
c. hyperbolic.
d. exponential.

35. During which phase of the growth curve might growth occur without a net increase in the viable count, and the production of secondary metabolites be common?
a. Lag.
b. Exponential.
c. Stationary.
d. Death.

36.Organisms that grow above 45-50ºC but not 80ºC are called
a. mesophiles.
b. thermophiles.
c. psychrophiles.
d. extreme thermophiles.

37. You have grown a bacterium in broth whose relationship to oxygen is unknown to you. You have removed the culture from the incubator without shaking it and note that growth is present throughout the tube. You conclude that it is
a. an obligate aerobe.
b. microaerophilic.
c. a facultative aerobe.
d. an obligate anaerobe.

38. Which of the following antibiotics damages the peptidoglycan of prokaryotes?
a. Polymyxin B.
b. Penicillin.
c. Streptomycin.
d. Tetracycline.

39. An organism which uses organic compounds as an energy source is most properly termed
a. a heterotroph.
b. a chemotroph.
c. a phototroph.
d. an autotroph.

40. The term photoheterotroph has no meaning since all phototrophs are also autotrophic.
True
False

41. The recognized sourcebook on prokaryote taxonomy is
a. the American Type Culture Collection.
b. the National Type Culture Collection.
c. Bergey's Manual of Determinative Bacteriology.
d. the American Society for Microbiology.

42. Which of the following would not be a trait for Caulobacter?
a. stalks.
b. holdfasts.
c. aerobic.
e. no motile stage.

43. Which of the following is an asexual spore of fungi?
a. basidiospore.
b. ascospore.
c. conidiaspore.
d. zygospore.

44.Which of the following is associated with aggregation of the cellular slime molds?
a. ATP.
b. cyclic-ATP.
c. AMP.
d. ADP.

45. The haploid stage of fungi is usually dominant in the fungal life cycle.
True
False

46. (10 points) Make a drawing of a typical bacterial growth curve. Label (a) the lag phase, (b) the exponential phage, (c) the stationary phase, and (d) the death or decline phase. Be sure to label the axes correctly.
Match the organism with the disease. Questions 47-51 are 1 point each.

47. Mycobacterium tuberculosis a. Syphilis

48. Treponema palladiu b. Tuberculosis

49. Clostridium tetani c. Lock jaw

50. Yersinia pestis d. Scarlet fever

51. Streptococcus pyogenes e. Bubonic plague