Ch 35

1. Vector-borne transmission can be either external or internal. In external (mechanical) transmission, the pathogen is carried A. on a fomite. B. on the body surface of a vector. C. within the vector. D. All of the choices are correct.

2. In which of the following situations did disease develop due to vertical transmission of the pathogen? A. A fetus develops listeriosis after unpasteurized cheese infected with Listeria bacteria is consumed by the mother during pregnancy B. A traveler develops gastroenteritis after drinking water that is contaminated with Escherichia coli bacteria C. A dog develops rabies after being scratched during a fight with a raccoon that carries the virus D. A hospitalized patient develops MRSA bacteria in a wound following surgery

3. A person who is infected with a potential pathogen fails to develop signs or symptoms of disease. This correlates with initial microbial dose, microbial lethality, and/or replication rate of the pathogen. A. low; high; low B. low; low; high C. high; low; low D. high; low; high

5. An inanimate object that may be contaminated with a pathogen is called a ________. A. vector B. fomite C. zoonoses D. None of the choices are correct.

6. Which of the following is a facultative, rather than obligate, intracellular pathogen? A. Chlamydia B. Brucella C. Rickettsia D. All of the choices are correct.

8. One example of infectious disease transmittion by a fomite is A. a child developing a cold after playing with a toy that harbored rhinovirus. B. a baby born with congenital syphilis from an infected mother. C. a teenager with severe acne due to propionibacteria growing in sebaceous glands. D. None of the choices are correct.

10. Which of the following features of a pathogen is not considered to be a virulence factor when establishing infection within host? A. Pigment production B. Attachment fimbriae C. Slime layer D. Protein spikes

12. All of the following situations are passive modes of penetration for the invasion of host tissues by opportunistic pathogens EXCEPT A. a child falling and scraping her knee. B. a firefighter receiving third-degree burns on the skin. C. a hiker being bitten by a tick. D. a bacterium adhering to intravenous tubing, forming a biofilm.

23. Listeria monocytogenes propels itself through mammalian host cells using A. a modified form of gliding motility. B. host cell actin and other cytoskeletal proteins. C. periplasmic flagella. D. fimbriae-based twitching motility.

24. The toxic component of lipopolysaccharide is called _________. A. lipid A B. exotoxin C. hemolysin D. O antigen polysaccharide

25. The characteristics of a pathogen that determine its virulence include which of the following? A. Pathogenicity B. Invasiveness C. Infectivity D. All of the choices are correct.

26. Pathogenicity islands are typically associated with A. genes encoding tRNA. B. genes encoding rRNA. C. G+C content similar to the rest of the bacterial genome. D. None of the choices are correct.

27. Which of the following is not a biological effect associated with endotoxin? A. Coagulation B. Paralysis C. Fever D. Fibrinolysis

28. Endotoxin is released when A. Gram-negative pathogens lyse or divide. B. cells are starved for iron. C. cells are lysogenic for the beta phage. D. All of the choices are correct.

29. Which of the following is not a characteristic of lipid A? A. Heat stable B. Toxic in nanogram amounts C. Weakly immunogenic D. Neurotoxic

30. Endotoxins include which of the following? A. Diphtheria toxin B. Lipopolysaccharide C. Tetanus toxin D. Botulinum toxin

31. A patient develops a high fever due to a Gram-negative pathogen. Which of the following is a certain mediator of illness in this case? A. Endotoxin B. Exotoxin C. Both endotoxin and exotoxin D. Neither endotoxin nor exotoxin

32. Bacteria within biofilms exchange A. plasmids. B. quorum-sensing molecules. C. nutrients. D. All of the choices are correct.

34. Place the events associated with each stage of infectious disease in the correct order with regard to time. Prodromal stage Incubation period Convalescence Illness period

35. Your brother mentions that several days ago he began to feel as if he was coming down with a cold, but now is no longer experiencing any signs or symptoms and feels fine. Having just studied the infectious disease process in your microbiology course, you immediately recognize that he is describing the phase of illness. A. prodromal B. convalescent C. acute D. incubation

41. The condition in the host that results from pathogenic parasitic organism growing and multiplying within or on the host is called A. an infection. B. an infectious disease. C. pathogenesis. D. All of the choices are correct.

42. The final outcome of most host-parasite relationships depends on A. the number of organisms present in or on the host. B. the virulence of the organism. C. the host's defenses. D. All of the choices are correct.

43. Which of the following has no effect on the outcome of the host-parasite relationship? A. The number of parasites on or in the host B. The virulence of the parasite C. The defenses of the host D. All of the choices are correct.

44. Any organism that can cause disease in the host after direct interaction is a(n) A. focal pathogen. B. opportunistic pathogen. C. primary pathogen. D. secondary pathogen.

46. If a symbiont either harms or lives at the expense of another organism, the relationship is called _________. A. symbiosis B. parasitism C. commensalism D. pathogenicity

47. An animal that is infected with a parasitic organism that can also infect humans is called a(n) ________ host. A. reservoir B. endoparasitic C. transfer D. intermediate

48. Which of the following must a pathogen possess in order for it to be successful at causing infectious disease? A. Ability to be transported initially to the host B. Ability to exit the host C. Ability to adhere to, colonize, or invade the host D. Ability to damage the host E. All of the choices are correct.