Lab quiz 6a.txt

  1. First step for unknown identification
    obtain a pure culture
  2. Second step for unknown identification
    gram stain
  3. Info you get from a gram stain (3)
    Gram reaction, cell shape, cell arrangement
  4. why must cells be in log phase for gram staining?
    old cultures of gram positive bacteria may appear as gram negative because there is not enough nutrients left after log phase and they can't retain crystal violet
  5. What 4 genus can fix nitrogen?
    Rhizobium, azobacter, cyanobacter, clostridium
  6. Symbiosis
    living together
  7. Commensalism
    the microbe benefits but the host is unaffected
  8. Mutualism
    both organisms benefit
  9. Parasitism
    microorganism benefits and the host suffers
  10. nitrogen fixation
    conversion of atmospheric nitrogen into usable compounds
  11. Plants that nitrogen fix
    leguminous (pea, bean, soybean, alfalfa, clover)
  12. Bacteria that nitrogen fix
    rhizombium and bradyrhizobium (G - rods)
  13. Staphylocoocus feed on
    saprophyte and parasite of the skin and mucus membrane
  14. Staphylococcus gram
    positive cocci in clusters (grapes)
  15. Staphyloccocus morphology
    medium sized, off white to yellow-orange colonies
  16. staphylococcus oxygen requirement
    facultative anaerobe
  17. Staphylococcus NaCl
  18. Do staph produce catalase
  19. Pathogenic staph
    staph aureus
  20. Staph aureus
    Wound infections, pnemonia, toxic shock syndrome, food poisoning
  21. Non pathogenic staph
    staph epidermidis and staph saprophyticus
  22. Staph epidermidis
    nosocomial infections
  23. Staph saprophyticus
    Urinary Tract Infections
  24. Do pathagenic or non pathegenic staph produce coagulase?
  25. Coagulase
    clots blood plasma to get past the hosts defense
  26. Streptococci food
    saprophytes and parasites
  27. Strep gram
    Gram + cocci in chains or pairs
  28. Strep oxygen requirement
    facultative anaerobe
  29. Strep fermentation
    lactose fermenters
  30. Strep morphology
    small, white, drop-like, mucoid, unpigmented colonies
  31. Does strep produce catalase?
  32. does Strep have salt tolerance?
  33. Hemolysins
    extracellular enzymes that lys RBC
  34. Alpha hemolysins
    partially lyse RBC and reduce hemoglobin to methemoglobin
  35. Beta hemolysins
    completley lyse RBC
  36. Gamma hemolysins
    no lysis
  37. Does pathogenic or non-pathogenic staph produce hemolysins?
  38. Group A Strep example
    S. pyogenes
  39. S. Pyogenes disease
    Strep throat
  40. Group A strep hemolysis
  41. Group B strep example
    S. agalactiae
  42. S. Agalactiae diseases
    impetigo, acute endocarditis, meningitis
  43. Group B strep hemolysis
  44. Group C strep diseases
    less serious
  45. Group C strep hemolysis
  46. Group D strep
  47. Group D strep hemolysis
    Beta-- may also be alpha or gamma
  48. Group D strep diseases
    endocarditis, meningitis, UTI
  49. Viridians hemolysis
  50. viridians disease
  51. Pneumococci hemolysis
  52. pneumococci diseases
  53. Staph tests
    Mannitol Sugar Agar (MSA), Coagulase test, Novobiocin test
  54. Strep Tests
    Hemolytic, Bile solubility, antibiotic susceptability, CAMP, Bile- esculin hydrolysis, NaCl tolerance
  55. Mannitol Salt Agar Test
    selects for staph due to high salt concentration and indicates mannitol fermentation by color change to yello
  56. Coagulase Test
    detects enzyme coagulase which converts fibrinogin to fibrin forming a clot. if a clot is formed, coagulase is present and the staph is pathogenic
  57. Novobiocin sensitivity test
    determines between non-pathogenic staph; s. epidermidis is resistant to novobiocin and will continue to grow in its presence
  58. Hemolytic Test
    determines hemolysis of Strep
  59. Bile Solubility Test
    Bile Salts lyse only strep pneumoniae; if the unknown is lysed then it is pneumonia
  60. Antibiotic Susceptibility Tests
    determines resistance to antibiotics to determine between groups of strep
  61. Group A strep are sensitive to___
  62. Strep Pneumonia are sensitive to___
  63. Group C strep are sensitive to___
  64. Bile-esculin hyrdolysis Test
    Group D strep hydrolyzes bile esculin into esculetin and glucose; esculetin is detected by adding ferric citrate
  65. NaCl Test
    Group D strep are salt resistant and will grow in NaCl broth making it turbid
Card Set
Lab quiz 6a.txt
Microbiology 221 Lab Quiz 6a