Micribiology Exam 3

The flashcards below were created by user lythia on FreezingBlue Flashcards.

  1. Host
    an organism that harbors another organism
  2. Symbiosis
    association between 2 (or more) species (meaning "living together")
  3. Mutualism
    both members of the assocition benefit from the relationship
  4. Commensalism
    one benefits and the other one neither benefits nor is harmed
  5. Parasitism
    parasite benefits from the relationship while the host is harmed by it
  6. Antagonism
    both species harm each other wihout either benifitting
  7. Opportunism
    some species of organisms that do not usually cause disease but do so under certain conditions
  8. Contamination
    microorganisms are present on inaminate objects or on surfaces of the skin or mucous membranes of the host, some with a capacityto invade host tissues
  9. Infection
    multiplication of any parasitic organism within or on the host's body
  10. Infestation
    type of infection that used to refer to presence of large parasites in or on the body
  11. Disease
    occurs when an infection disrupts the normal functioning of the host
  12. Pathogenicity
    • capacity to produce disease
    • depends on the ability of the organism to invade a host, multiply in the host, and aoid being damaged by the host's defenses
    • the larger the number of pathogens, the greater the chances of causing disease
  13. Virulence
    • refers to intensiyt of the disease (how hard it hits) produced by pathogens, and it varies among different microbial species and even among members of the same species of pathogen
    • virulence of a pathogen can increase by animal passage, the rapid transfer of the pathogen through animals of a species susceptible to infection by that pathogen
    • can be decreased by attenuation
  14. Attenuation
    can be achieved by repeated subculturing on lab media or by transposal of virulence
  15. Transposal of virulence
    • lab technique in which a pathogen is passed from its normal host to a new host species and then passed sequentially through many individuals of the new species
    • eventually the pathogen adapts completely to the new host and is no longer virulent for the original host
    • used in mumps, measles vaccin preparation
  16. Normal microflora
    • organisms that live on or in the body but do not cause disease
    • also known as microbiota
    • most are commensals
  17. Resident microflora
    • comprose of microbes that are always present on or in the human body
    • highly adapted to prevailing conditions
  18. Transient Microflora
    • comprise of microbes that can be present under certain conditions in any of the locations where resident microflora are found
    • persis for hours to months depending upon the existing conditions (favorable)
    • among the residen and transient micrlora, you can find some species that do nt usually cause disease, but can do so under certain conditions (opportunists)
  19. Koch's postulate
    • specific causative agent must be observed
    • agent must be isolated and grown in pure culture
    • hosts must get the same disease when inoculated
    • agent must be re-isolated and show to be the same causative agent
  20. Latrogenic diseases
    • also known as nosocomial infections
    • caused by infections acquired at hospital
    • staphylococcus aereus infection
  21. Idiopathic diseases
    cause is unknown
  22. Virulence factors
    • structural or physiolgocal characteristics that help organisms cause infection and disease
    • pili for adhesion to cells and tissue
    • enzymes that eitehr help in evading host defenses or protect the organism from host defenses
    • toxins that can directly cause disease
  23. Biofilms
    specialized communities (colonies) of bacteria that utilize mass-produced glycocalyx to adhere to surfaces and bild a hospitable environment
  24. Growth in the host
    • adherence
    • host defense evasion
  25. Capsules
    • structures made of glycocalyx that surround the bacterial cell
    • hydrophobic nature protect the bacterial cell against harsh environments
    • can resist phagocytosis
  26. Coagulases
    • enzymes that clot blood plasma
    • can produce favorable environmentfor pathogen
    • can hinder mobility of leukocytes
  27. Hyaluronidase
    enzyme taht oxidizes hyaluronic acid, decreasing its viscosity and enabling the pathogen to penetrate deeper into the tissue
  28. Hemolysins
    enzymes that kill RBCs and release Fe2+
  29. Leukocidins
    enzymes that kill leukocytes
  30. Leukostatins
    interfere with the ability of leukocytes to engulf microorganisms that secrete the exotoxin
  31. Chemokine proteases
    enzymes that break down interleukins
  32. Damage to host cell
    • Direct- by release of toxins
    • Indirecty
  33. Endotoxins
    • toxins released from the pathogen at death, usually as a result of phagocytosis or degradation
    • bacterial endotoxins have nonspecific effects
    • can also cause tissue damage
  34. Mycolic endotoxin
    created when acid-fast bacteria are degraded
  35. O-antigen
    endotoxin that is crated when gram-negative bacteria are degraded
  36. Exotoxins
    • powerful toxins deliberately released by living pathogen (almost all gram-positive and some gram-negative), most are polypeptides
    • C. difficile's TcdA, B. anthracis' toxin complex, and C. botulinum's Botulinum toxin (bottom)
    • many have special attraction for special tissue
    • Enterotoxins
  37. Hyperimmune response
    • also known as autoimmune response
    • can cause damage to the host by overreaction or missing the target enirely
  38. Indirect- by release of toxins
    • usually by nutrient acquisition by the pathogen
    • pathogen out-competes host for nutrition
  39. Sign
    • characteristic of a disease that can be observed by examining a patient
    • include such things as swelling, redness, rashes, coughin, pus formation, runny nose, fever, vomiting and diarrhea
  40. Symptom
    • characteristic of a disease that can be felt or experienced only bt the patien
    • include such things as pain, shortness of breath, nausea, sore throat, headache and malaise (discomfort)
  41. Syndrome
    Combo of signs and symptoms that occur together and are indicative of a particular disease or abnormal condition
  42. Sequalae
    after effects that some diseases leave even after recover (eg. effects following infection by polio virus)
  43. Epidemiology
    study of factors and mechanisms involved in the frequency and spread of diseases and other health related problems within population of humans, animals or even plants
  44. Etiology
    refers to the causation of a disease
  45. Incidence of a disease
    number of new cases contracted within a set population during a specific period of time
  46. Prevalence of a disease
    total number of people infected withina a population at any time
  47. Morbidity
    rate typically expressed as the number of cases (individuals) per 100k people/year infected by the same disease or pathogen
  48. Mortality
    rate typically expressed in terms of individuals/100k that have been killed by some disease or pathogen
  49. Endemic
    infectious agent is present continually in the population of a particular geographic area, but both the humber of reported cases and the severity of the diesease remain low to constitute public health problem
  50. Epidemic
    • arises when a disease suddenly has a higher-than-normal incidence in a population
    • then the moribity rate or motrtality rate of both become high enough to cause public health problem
  51. Pandemic
    occurs when an epidemic spread world wide
  52. Sporadic disease
    occurs in a random, unpredictable manner, involving several isolated cases that pose no great threat to the population as a whole
  53. Common source outbreak
    epidemic that arises from contact with contaminated substances
  54. Propagated epidemic
    • arises from direct person-to-person contacts of horizontal transmission
    • pathogen movies from infected to uninfected individual
  55. Infection reservoirs
    • Human
    • Animal
    • Non-living, soil, and water
  56. Contact transmission
    • Direct contact
    • Indirect contact by fomites
    • Droplets
  57. Vehicle transmission
    • Waterborne
    • Airborne, including dust particles
    • Foodborne
  58. Vector transmission
    • mechanical (on insect bodies)
    • Biological
  59. Problems in disease transmission
    • disease cycles
    • herd immunity
  60. Controlling disease transmission
    • Isolation
    • Quarantine
    • large-scale immunization
    • vector control
  61. Notifiable diseases
    • infectious diseases that are potentially harmful to the public's health
    • Nationally Notifiable Infectious Diseases
  62. Exogenous infections
    caused by organisms that enter the patient from the environment
  63. Endogenous infections
    caused by opportunists among the patient's own microflora
  64. Nosocomial infection risks
    • susceptibility
    • transmission
    • universal precautions
Card Set:
Micribiology Exam 3
2011-11-05 22:12:58
BIOL 209

exam 3
Show Answers: