abcd

31. Which of the following methods will NOT sterilize? a) 100°C boiling water for 30 minutes b) formalin for 10 hours c) dry heat at 171°C for 2 hours d) steam 121 !C under pressure for 15 to 20 minutes

a) 100 !C boiling water for 30 minutes

3. What is present within the prokaryote cell: a) mitochondria b) golgi bodies c) sterols d) endoplasmic reticulum

none of these answers are correct

2. Mark the correct statements: a) Streptococcus pyogenes is gram-negative rod b) serotyping of bacteria evaluates the patients antibody response to infection c) bacteriophages are bacterial viruses d) Neisseria has branched filamentous appearance

a) Streptococcus pyogenes is gram-negative rod c) bacteriophages are bacterial viruses

17. A virulence factor is one which a) allows a microbe to invade and establish itself on the host b) allows a host to evade infection c) normal flora use against invading microorganisms d) invading organisms use against normal flora

a) allows a microbe to invade and establish itself on the host

40. How are microbes able to resist immunologic clearance? a) by antigenic variation b) by inactivation od antibody c) by intracellular growth d) by lysing phagocytic cells

a) by antigenic variation b) by inactivation od antibody c) by intracellular growth d) by lysing phagocytic cells

36. Which macromolecule(s) is (are) currently being used as a vaccine in humans? a) capsular polysaccharides b) recombinant surface antigens c) inactive exotoxins d) DNA-based

a) capsular polysaccharides b) recombinant surface antigens c) inactive exotoxins

5. Mark the bacterial cell wall component(s) that contribute to virulence by protecting the bacteria from immune responses: a) capsule b) pili c) lipid A d) lipoteichoic acid

a) capsule

21. Microbial resistance to drugs is acquired through: a) conjugation b) transformation c) transduction d) mutation

a) conjugation b) transformation c) transduction d) mutation

20. Sulfonamide drugs initially disrupt which process? a) folic acid synthesis b) transcription c) PABA synthesis d) protein synthesis

a) folic acid synthesis

9. Plasmid a) is transferred by conjugation as a single-stranded molecule b) can be integrated into the bacterial chromosome c) can incorporate chromosomal DNA d) can be transferred by conjugation, transduction, transformation

a) is transferred by conjugation as a single-stranded molecule b) can be integrated into the bacterial chromosome c) can incorporate chromosomal DNA d) can be transferred by conjugation, transduction, transformation

11. Strict pathogen(s) always associated with human disease is (are): a) mycobacterium tuberculosis b) neisseria gonorrhoeae c) staphylococcus aureus d) candida albicans

a) mycobacterium tuberculosis b) neisseria gonorrhoeae

15. On the same day the clinical laboratory identifies two strains of the same bacterial species. One of these strains has pili on the surface; the other does not. In terms of the clinical status of the two patients it is likely that: a) the patient with the piliated strain is ill, the other patient is not b) the patient with the piliated strain is not ill, the other patient is c) both patients are ill since pili do not correlate with virulence d) patient with the piliated strain is a child, the other patient is an adult

a) the patient with the piliated strain is ill, the other patient is not

39. The Western blot test differs from ELISA tests differs from ELISA tests in which of the following ways? a) Western blot differs for antigen only b) Antibodies to individual antigens can be identified in Western blot c) Western blot detects antibody earlier than ELISA tests d) Only ELISA test involves enzyme labels

b) Antibodies to individual antigens can be identified in Western blot

34. Poor skin tests to a range of microbial antigens such as tuberculin and mumps indicate a deficiency of: a) NK cells b) T-cells c) B-cells d) phagocytosis

b) T-cells

28. If the immune response in an infected host can partially, but not completely eradicate the pathogen, the host may experience: a) an acute illness b) a chronic illness c) an opportunistic infection d) a transient infection

b) a chronic illness

19. Drugs that prevent the formation of the bacterial cell wall are a) quininolones b) beta-lactams c) tetracyclines d) aminoglycosides

b) beta-lactams

7. Which compound(s) would be considered a signature molecule of the bacterial endospore? a) peptidoglycan b) dipicolinic acid c) propionic acid d) lactic acid

b) dipicolinic acid

10. Random packaging of genes occurs during a) specialized transduction b) generalized transduction c) conjugation d) sporulation

b) generalized transduction

27. A person with a severe cold sneezes into a bath towel. Later, a family member takes a shower and dries himself with the same bath towel. As he dries his face, this individual becomes infected with the cold virus and develops a cold himself. This is an example of: a) direct contact transmission b) indirect contact transmission c) airborne transmission d) vector transmission

b) indirect contact transmission

1. Which of the following organisms have mycolic acids in their cell walls: a) staphylococcus b) nocardia c) mycobacterium d) klebsiella

b) nocardia c) mycobacterium

22. R factors are ______ that contain a code for ______. a) genes, replication b) plasmids, drug resistance c) transposons, interferon d) plasmids, conjugation

b) plasmids, drug resistance

24. Which of the following is the most accurate definition of "infection"? a) the presence of microorganism in a particular location b) the survival and reproduction of microorganisms in a host c) the disruption of normal host functions by microorganisms d) appearance of symptoms in a host, caused by microorganisms

b) the survival and reproduction of microorganisms in a host

37. Which of the following vaccines has actually been implicated in causing the disease it is designed to prevent? a) pneumococcus vaccine b) Salk polio vaccine c) Sabin oral polio vaccine d) tetanus vaccine

c) Sabin oral polio vaccine

26. Assuming an effective vaccine exists, which of the following diseases would be most likely to be controlled through a carefully designed vaccination program? a) a disease using various animal reservoirs b) a disease using both animal and human reservoirs c) a disease using human reservoirs only d) a disease using environmental reservoirs

c) a disease using human reservoirs only

13. Characteristics of a bacterial capsule include: a) all bacteria have one b) it is composed of peptidoglycan c) it is an important mechanism for protecting a bacteria against ingestion by PMNs d) it is what causes the gram stain reaction

c) it is an important mechanism for protecting a bacteria against ingestion by PMNs

6. Mark the bacterial cell wall component(s) that contribute to virulence by eliciting fever and shock: a) capsule b) pili c) lipid A d) lipoteichoic acid

c) lipid A

38. Antibody to an immunogen can facilitate phagocytosis of that substance. The term used to describe this phenomenon is: a) agglutination b) precipitation c) opsonization d) antibody affinity

c) opsonization

4. What are the structures involved in transport of materials across the outer membrane of the gram negative bacteria? a) lipopolysaccharides b) periplasmic space c) porin proteins d) prion proteins

c) porin proteins

23. The MIC is the ______ of a drug that is required to inhibit growth of a microbe. a) largest concentration b) standard dose c) smallest concentration d) lowest dilution

c) smallest concentration

29. In a bacterial exotoxin: a) the A subunit allows the toxin to bind to the surface of specific host cells b) the A subunit is part of the outer bacterial membrane, released when the bacterial cell dies c) the A subunit is able to interfere with a specific host cell activity, once it has been taken into the host cell d) we expect the A subunit for all exotoxins to operate in the same manner

c) the A subunit is able to interfere with a specific host cell activity, once it has been taken into the host cell

14. As a budding basic scientist you work in a research laboratory and discover a chemical that removes the cell wall from bacteria but leaves the organism undamaged otherwise. Things that the bacteria will lose because of this include: a) the ability to stain gram positive: all will look gram negative b) the ability to move c) the ability to have a gram stain result d) the ability to attach to other cells

c) the ability to have a gram stain result

8. Which mechanism(s) may be used by a bacterial cell for the exchange of genetic material? a) Okazaki fragments b) meiosis c) transformation d) lysogeny

c) transformation

32. All of the following are sporicidal EXCEPT a) glutaraldehyde b) ethylene oxide c) formaldehyde d) alcohol

d) alcohol

18. Exotoxins differ from endotoxins in that exotoxins a) are composed of lipopolysaccharides b) are stable at 56°C c) cannot be converted to toxoids d) are secreted from living cells

d) are secreted from living cells

16. Identify the sterile (microbe-free) anatomical site from the list below. a) vagina b) urethra c) rectum d) bladder

d) bladder

33. During acute inflammation, there is a burst of oxygen consumption (respiratory burst) in neutrophils. This is an essential step for which of the following events? a) attachment to the endothelial cells b) opsonization of bacteria c) phagocytosis of bacteria d) generation of microbicidal activity

d) generation of microbicidal activity

25. Which of the following is an example of an opportunistic infection? a) normal flora living in the intestine of an animal b) the transmission of an airborne pathogen to a new host, when an infected host sneezes c) an infection caused when a previously non-pathogenic organism mutates into a pathogen d) infection of the blood caused when a cut on the skin allows a normally skin-dwelling microorganism to enter the blood

d) infection of the blood caused when a cut on the skin allows a normally skin-dwelling microorganism to enter the blood

12. A person who has a normal healthy immune system acquires a new strain of E.coli that now lives in his gastrointestinal tract. This individual is not ill. A second person with an acute leukemia and no white blood cells acquires the same organism, develops diarrhea followed by hypotension, bacteremia, sepsis, and death. This organism is: a) normal flora for both individuals b) a pathogen for both individuals c) an opportunistic pathogen for both individuals d) one with a low degree of virulence

d) one with a low degree of virulence

35. Which of the following penicillins is (are) "-lactamase resistant? a) amoxycillin b) penicillin V c) penicillin G d) oxacillin

d) oxacillin

30. If Gram-negative bacteria cause an infection of the blood, killing these bacteria rapidly with an antibiotic might result in: a) the release of exotoxin b) the release of peptidoglycan from the cell walls of these bacteria c) the release of tissue degrading enzymes by the bacteria d) the release of lipopolysaccharide by the bacteria

d) the release of lipopolysaccharide by the bacteria