Microbiology 301
Final Exam
You will be given an examination and a computer answer sheet. Make sure your name is on both the question and answer sheet. MARK ANSWER ON BOTH AND HAND BOTH IN.
The COMPUTER SHEET WILL NOT BE RETURNED and you are RESPONSIBLE for the correct transfer of your answers to the computer answer sheet.
The questions will be returned along with an individual student score report in a room in the laboratory area (number to be announced). If you wish to have your examination returned privately, give the proctor of the examination a note to that effect.
Choose the ONE best answer.
1. Which of the following is best described as an opportunist?
A. Corynebacterium diphtheriae
B. Neisseria gonorrhoeae
C. Pseudomonas aeruginosa
D. Schistosoma
E. Yersinia pestis
2. The function of IgA protease is to...
A. bind to the Fc receptor of IgA.
B. bind to the Fab region of IgA.
C. stimulate the synthesis of IgA.
D. destroy IgA.
E. destroy plasma cells that are programmed to make IgA.
3. Which of the following pathogens can cause severe illness without evading the immune response?
A. Clostridium botulinum
B. Neisseria gonorrhoeae
C. Mycobacterium tuberculosis
D. Salmonella typhi
E. Streptococcus pneumoniae
4. Which of the following statements about endotoxin is FALSE?
A. It is readily destroyed by heating.
B. It is produced by Gram negative rods.
C. It is produced by Gram negative cocci.
D. In high quantities it can be fatal.
E. There is no vaccine to protect against it.
5. Which of the following produces a neurotoxin that causes an uncontrollable muscle contraction by blocking nerve inhibition?
A. Clostridium botulinum
B. Clostridium tetani
C. Corynebacterium diphtheriae
D. Escherichia coli O157:H7
E. Neisseria gonorrhoeae
6. Which of the following is responsible for the symptoms of schistosomiasis?
A. Production of endotoxin
B. Production of exotoxin
C. Inflammation and the resulting scarring
D. High fever resulting in neurological damage
E. Blood loss
7. Which of the following defines a pandemic?
A. A newly occurring disease.
B. A disease that has an exceptionally high mortality rate.
C. A disease that has an exceptionally high morbidity rate.
D. A disease that is constantly present in a specific geographic area.
E. An epidemic that has spread around the world.
8. Which of the following is NOT a zoonotic disease?
A. Rabies
B. Plague
C. Ebola
D. Polio
9. A fomite is...
A. a non-living object that can be a source of infection.
B. a child or other individual who doesn't practice good hygiene.
C. an insect that transmits disease.
D. an animal that transmits disease through a bite.
E. All of the above are fomites
10. Which of the following is transmitted by a vector?
A. E. coli O157:H7
B. Mycobacterium tuberculosis
C. Neisseria gonorrhoeae
D. Polio virus
E. Yersinia pestis
11. Which of the following about Yersinia pestis is FALSE?
A. Bubonic plague is not infectious to others.
B. Untreated, the mortality rate of pneumonic plague is less than that of bubonic plague.
C. Plague still occurs in the United States.
D. Bubonic plague and pneumonic plague are both caused by the same type of organism.
E. Yersinia pestis can survive in macrophages.
12. Which of the following about Mycobacterium tuberculosis is FALSE?
A. Strains are becoming resistant to the most useful antibiotics.
B. Most people who are infected never develop the disease.
C. Over 1/3 of the world population is infected with the organism.
D. Treatment normally involves taking antibiotics for two weeks.
E. People in the US aren't routinely vaccinated.
13. Antibiotics can do which of the following?
1. Inhibit the growth of bacteria
2. Kill bacteria
3. Destroy viruses
4. Stop viral replication
A. 1, 2 B. 1, 4 C. 2, 3 D. 3, 4 E. All of the above
14. An immunocompromised person comes in with a Staphylococcus infection. An antibiotic with which of the following characteristics would be most appropriate?
1. Broad spectrum
2. Narrow spectrum
3. Bactericidal
4. Bacteriostatic
5. Low therapeutic index
A. 1, 3, 5 B. 2, 4, 5 C. 2, 3 D. 2, 3, 5 E. 1, 3
15. The significance of the beta-lactam ring in penicillin is that...
A. it can be chemically modified to increase the spectrum of activity of the drug.
B. penicillinases can cleave it, thus inactivating the drug.
C. it is the site that binds the 70S ribosome.
D. its presence causes penicillin to be sensitive to stomach acid.
E. All of the above
16. Which of the following about antibiotic resistance is FALSE?
A. Vancomycin resistant enterococci (VRE) are resistant to all common antibiotics.
B. Methicillin resistant Staphylococcus aureus (MRSA) are resistant to all common antibiotics except vancomycin.
C. Neisseria gonorrhoeae is becoming increasingly resistant to some antibiotics.
D. R plasmids are only significant if they are acquired by a pathogen.
E. Taking antibiotics for less than the prescribed time lessens
the likelihood of pathogens becoming antibiotic-resistant.
17. Which of the following about use of antibiotics is FALSE:
A. Taking antibiotics can make you more susceptible to other infections.
B. Some people are allergic to certain antibiotics such as penicillin.
C. Some antibiotics occasionally cause adverse reactions such as hearing loss.
D. Antibiotics should not be taken for strep throat, because it is a relatively minor disease.
E. Misuse of antibiotics has resulted in greater numbers of
antibiotic resistant organisms
18. Salvarsan, the chemotherapeutic drug developed by Erlich, was used to treat which disease?
A. Gonorrhea
B. Tuberculosis
C. Syphilis
D. Smallpox
E. Plague
19. Which of the following statements is TRUE?
A. Staphylococcus and Streptococcus are both catalase positive.
B. Staphylococcus is an facultative anaerobe whereas Streptococcus is an obligate fermenter.
C. Staphylococcus is found most commonly in the mouth, whereas Streptococcus is found most commonly on the skin.
D. Staphylococcus usually grows in chains, whereas Streptococcus usually grows in clusters.
E. Only Staphylococcus infections are considered
life-threatening.
20. Exfoliatin toxin produced by Staphylococcus aureus causes...
A. foodborne intoxication.
B. glomerulonephritis.
C. toxic shock syndrome.
D. necrotizing fasciitis.
E. scalded skin syndrome.
21. Which of the following about Staphylococcus aureus food poisoning is FALSE?
A. Live organisms must be ingested which then colonize the intestine and produce toxin.
B. Contaminated ham is a commonly implicated food product.
C. Not all Staph. aureus strains produce the toxin.
D. It can be prevented by hand-washing before preparing a meal.
E. Even Easter eggs can become contaminated with Staph.
22. Which of the following about M protein are TRUE?
1. It is produced by Streptococcus pneumoniae.
2. It protects organisms from phagocytosis.
3. It is a superantigen.
4. There are many different antigenic types.
5. It lyses red blood cells.
A. 1, 3, 4 B. 2, 4 C. 2, 3, 4, 5 D. 2, 3
23. Rheumatic fever is thought to be caused by which of the following?
A. A superantigen
B. A toxin but not a superantigen
C. Antibodies
D. Antibiotics
E. Infection of the heart tissue
24. Semmelweis used epidemiology to show that puerperal fever could be prevented by...
A. using antibiotics to rid carriers of the causative organism.
B. vaccination.
C. passive immunization.
D. handwashing.
E. B and C
25. Which of the following statements about the gastrointestinal tract is FALSE?
A. There is little normal flora in the small intestine.
B. The normal flora in the large intestine play a major role in excluding pathogens.
C. Approximately 9 liters of fluid per day are absorbed in the intestine.
D. The finger-like projections of the small intestine are called villi.
E. The majority of nutrient absorption occurs in the large
intestine.
26. Which of the following about cholera is TRUE?
A. It has been eradicated from the Western Hemisphere.
B. It is best treated by prompt antibiotic therapy.
C. The actual cause of death is severe dehydration.
D. Vibrio cholerae produces a cytotoxin that damages intestinal cells.
E. The disease is most commonly transmitted person to person.
27. Which of the following statements about Shigella is FALSE?
A. Shigella dysenteriae is the species that is most common in the U.S.
B. Shigella outbreaks can easily occur in daycare centers.
C. Shigella can invade intestinal cells.
D. Handwashing is an important means of preventing the
disease.
28 Which of the following statements about E. coli 0157:H7 is FALSE?
A. The toxin made by the strain is nearly identical to Shiga toxin.
B. The toxin is encoded by bacteriophage DNA.
C. It most likely has a high infectious dose.
D. Thorough cooking will destroy the organism.
E. It can cause life-threatening kidney damage.
29. Which of the following about Salmonella gastroenteritis is FALSE?
A. Untreated cases may go on to develop typhoid fever.
B. Outbreaks commonly involve improperly cooked poultry.
C. Unbroken raw eggs can be a source of infection.
D. Symptoms include diarrhea and abdominal pain.
E. It can be prevented by washing surfaces that have been used to
prepare poultry before preparing other foods.
30. Which of the following statements about Giardia is FALSE?
A. Clear mountain stream water can be a source of infection.
B. The more severe the diarrhea that an infected person has, the greater the likelihood they can transmit the disease.
C. The symptoms of Giardia are thought to be due to the mechanical damage caused by the millions of organisms attached to the small intestine.
D. The trophozoites have the appearance of a smiling person wearing glasses.
E. The cysts can survive in the environment for extended periods
of time.
31. Which of the following statements about enveloped viruses is FALSE?
A. The envelope is usually derived from the host cell membrane.
B. They generally lyse their host cells.
C. They are less likely to survive in the environment than naked viruses.
D. They can enter a host cell by fusion or endocytosis.
Use the following to answer questions 32 through 35.
A. Influenza virus
B. Herpes virus
C. Polio virus
D. More than one of the above
E. None of the above
32. Transmission is generally fecal-oral.
33. People who have no symptoms can shed the virus.
34. Occurs more commonly in the winter months.
35. Drugs can destroy the virus and cure the infection but they
are expensive.
36. Which of the following statements is FALSE?
A. Before polio vaccines, an infected person in the U.S. was more likely to develop paralytic polio than was a person in a developing country.
B. Influenza vaccines are given yearly because the body doesn't have a strong enough immune response to the vaccine to be protective for more than one year.
C. People who have influenza are more susceptible to infections by Streptococcus pneumoniae.
D. Herpes simplex 2 (genital herpes) can be transmitted to the
oral region.
37. You want to do a study to determine the percentage of the population that has antibodies to herpes simplex virus (HSV). Which of the following techniques would be most useful?
A. ELISA
B. PCR
C. Southern blot
D. Northern blot
E. Cloning
38. The type of antibody that is most prevalent in the serum is:
A. IgA
B. IgD
C. IgE
D. IgG
E. IgM
39. The role of the type of T cell that the Human Immunodeficiency Virus (HI) infects is to...
1. stimulate B cells and T cells that are "seeing" antigen to divide.
2. kill the cell that is presenting foreign antigen.
3. recognize antigen presented in MHC Class I.
4. recognize antigen presented in MHC Class II.
A. 1, 3 B. 1, 4 C. 2, 3 D. 2, 4 E. 1, 2
40. Which of the illnesses following could NOT be prevented through better sanitation?
A. Giardia
B. Schistosomiasis
C. Cholera
D. Polio
E. Diphtheria
41. It is thought that some bacterial capsules cover complement proteins that are bound to the cell wall. This effect would interfere with...
A. opsonization.
B. antibody production.
C. recognition of the organism as foreign.
D. T helper cell response.
E. T cytotoxic cell response.
42. Which of the following statements is FALSE?
A. It is possible to identify bacteria by their capsule antigen(s).
B. Removal of the cell wall results in a loss of cell shape and/or lysis.
C. Pili are surface appendages that are used by some bacteria for cell attachment.
D. Of the various ways that bacteria allow entry of molecules into the cell, active transport is the only one that allows you to have more of a substance inside than outside.
E. Most of the genetic information of bacteria is encoded on plasmids.
43. Which of the following statements about bacterial growth is FALSE?
A. From a mixed culture it is possible to isolate a pure culture of a particular species even if there is only one bacterium of that species in a population numbering 1-10 million.
B. Growth is an asexual process.
C. Environmental and nutritional factors can influence the doubling time of a culture.
D. Pathogenic bacteria would be expected to be mesophilic chemoautotrophs.
E. Cells can enter the stationary phase of growth even if carbon and energy are still available.
44. Which of the following statements is FALSE?
A. More energy can be generated by a bacterium if it metabolizes a carbon source by aerobic respiration than by fermentation.
B. Most organisms that ferment produce the same metabolic end products.
C. In biology, a chemical that has become reduced has acquired a pair of electrons and protons.
D. Irrespective of the growth requirements of an organism, they must all make the same essential precursor molecules needed for macromolecule synthesis.
E. The product of one enzyme may be the substrate for another enzyme.
45. Which of the following statements is FALSE?
A. Messenger RNA is read in groups of 3 nucleotides at a time, each group called a codon.
B. Base pairing rules are more important in translation than they are in transcription.
C. In bacteria, an m-RNA may encode for more than one protein.
D. The role of t-RNA is to bring an amino acid to the site of protein synthesis.
E. An amino acid may be specified by more than one codon.
46. Which of the following statements about bacterial macromolecules or their synthesis is FALSE?
A. Syntheses of the complementary strands are made in either the 5' to 3' or 3' to 5' direction, depending on which template strand is being used.
B. In contrast to DNA replication where synthesis is initiated at a specific site, transcription is initiated at many sites called promoter regions.
C. During transcription, only part of the genetic information encoded in DNA is expressed as specific RNA molecules.
D. Cellular RNA is always single-stranded.
E. The products of transcription are t-RNA, m-RNA and r-RNA.
47. Which of the following statements is FALSE?
A. If it were not for the proof-reading ability of DNA polymerase, the spontaneous mutation rate would be much higher than is observed.
B. Many chemical mutagens act by altering the base-pairing properties of a nucleotide.
C. Different genes within the same chromosome may have different mutation rates.
D. Mutations can only be considered detrimental to the survival of a species.
E. Dark repair involves some of the same enzymes used in DNA replication.
48. Which of the following statements about bacteriophage is FALSE?
A. Bacteriophage contain either DNA or RNA, never both.
B. Some phage can attach to the cell wall, others to the flagellum, and others to pili.
C. Temperate bacteriophage are associated with specialized transduction.
D. During the eclipse phase, infectious particles are present within infected cells.
E. Some bacteria owe their pathogenicity to harboring a prophage.