Micro - Lecture Final

  1. Type of cell that:

    One circular chromosome
    not in a membrane
    Peptidoglycan cell wall (bacteria)
    Binary fission
  2. Type of cell that: 

    Paired chromosomes in a nucleus
    Divides by mitosis
  3. Base pairs A --> T, C --> G
    All together forms nucleotide
    Double stranded
  4. Single stranded molecule
    Contains ribose
  5. Shapes and arrangements of

    Cocci (Staph/Strep)
    • Shape = spherical
    • Arrangement: pairs, clusters, chains
  6. Shapes and arrangements of

    • Shape = rod
    • Arrangement: pairs, chains
  7. What is a porin?
    (proteins) form channels for entry and exit of solutes
  8. Difference between Gr+ and Gr- cell walls
    • Gram-Positive
    • THICK Peptidoglycan wall 

    • Gram-Negative
    • Thin Peptidoglycan wall
    • Plasma membrane
    • Periplasm
    • LPS (lipopolysaccharide)
    • Porins (proteins) form channels for entry and exit of solutes
  9. A substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction.
  10. What is the function of ATP?
    Transports chemical energy within cells for metabolism
  11. Growth occurs only where high concentrations of O2 have diffused into the medium
    Obligate Aerobes – Oxygen Required
  12. Growth is best where most O2 is present, but occurs throughout tube
    Facultative Anaerobes – Both aerobic and anaerobic, greater with O2
  13. Growth occurs only where there is no O2
    Obligate Anaerobes – Only Anaerobic, ceases in the presence of O2
  14. Growth occurs evenly; O2 has no effect
    Aerotolerant Anaerobes – Only Anaerobic, but continues in the presence of O2
  15. Growth occurs only where a low concentration of O2 has diffused into medium
    Microaerophiles – Only Aerobic growth, O2 required in low concentrations
  16. What is a biofilm and what does it do?
    • Microbial communities
    • Usually found on solid substrates submerged in or exposed to an aqueous solution
    • Cell to cell communication allows bacteria to coordinate their activity forming a functional community
    • Resists antimicrobials
  17. Name the stages of disease
    • Incubation period
    • Prodromal period
    • Period of Illness
    • Period of Decline
    • Convalescence
  18. The interval between initial infection and onset of symptoms (time depends on microorganism, virulence, number, host resistance)
    Incubation period
  19. This follows incubation (when you first start feeling lousy)
    Prodromal period
  20. The presence of severe symptoms
    Period of illness
  21. The symptoms subside (secondary infection vulnerability)
    Period of decline
  22. The time of recovery
  23. microbes normally present in and on the human body
    Normal microbiota
  24. What is the function of normal microbiota?
    • Prevent growth of pathogens
    • Produce growth factors (folic acid and vitamin K)
    • Resistance to ward off disease
  25. What are Opportunistic organisms?
    • Live outside normal habitat
    • Cause problems outside their habitat
  26. What is a Plasmid?
    Genetic strand (piece) of DNA
  27. What is the function of a Plasmid?
    manipulation of genes, mutations in viruses/bacteria
  28. disease constantly present in a population
  29. disease acquired by many hosts in a given area in a short time
  30. worldwide epidemic
  31. disease that occurs occasionally in a population (Typhoid)
  32. symptoms develop rapidly and end shortly after (Flu)
  33. disease develops slowly, continues for a long period and may reoccur (Malaria)
  34. spread of microbes, especially bacteria or their toxins in the blood, lungs or other tissues
  35. bacteria in the blood
  36. toxins in the blood
  37. viruses in the blood
  38. blood poisoning, especially that caused by bacteria or their toxins.
  39. acute infection that causes the initial illness (cold)
    primary infection
  40. opportunistic infection after a primary infection (pneumonia)
    secondary infection
  41. habitat in which the agent normally lives, grows, and multiplies, and from which they can be transmitted
  42. animal diseases that may be transmitted to humans
  43. arthropods, especially fleas, ticks, and mosquitoes
  44. hospital acquired infections
  45. the incidence of disease
  46. the proportion of deaths to population
  47. the study of the cause of a disease
  48. ability of bacterial cell to alter their surface antigens
    antigenic variations
  49. Characteristics of Exotoxin
    • produced within cell
    • bacteria must be functional
    • secreted
    • protein
    • typically Gram+
  50. Characteristics of Endotoxin
    • Lipid
    • Gram-
    • Not secreted
    • Part of the membrane of the cell
    • Causes problem once then cell dies and lyses
  51. leaves a clear zone around colony on blood agar

    strep pyogenes
  52. forms a green zone around colony on blood agar

    strep pneumoniae
  53. no hemolysis on blood agar
  54. What is meningitis?
    inflammation of the meninges
  55. What organism(s) cause meningitis?
    • Haemophilius influenza
    • Neisseria meningitides
    • Streptococcus pneumoniae
  56. What is the blood-brain barrier?
    separation of the circulating blood from the brain’s extracellular fluid
  57. What is the blood-brain barrier effect on treatment of infections
    Restriction of molecules crossing into the CSF
  58. What is encephalitis?
    inflammation of the brain
  59. Defenses of the human skin
    • Salt inhibits microbes
    • Lysozymes in sweat
  60. What role does sebum play in acne?
    • A lipid that clogs pores
    • Propionibacterium uses sebum as a nutritional source to grow
  61. What Staph and Strep organisms cause skin diseases?
    • Staph aureus
    • Staph epidermidis
    • Strep pyogenes
  62. What biochemical tests distinguish between Staph and Strep?
    Catalase test – Staph+, Strep-
  63. What biochemical tests distinguish between Strep species?
    Strep: hemolysis on blood agar
  64. What biochemical tests distinguish between Staph aureus and other Staph species
    coagulase test differentiates from other staph
  65. What bacteria cause intestinal disease and how does diarrhea occur?
    • Staph aureus: kills cells = diarrhea
    • Salmonella: inflammatory response = diarrhea
    • E. Coli: toxin is released when cell lyses = diarrhea
  66. How does Typhoid fever occur?
    • Salmonella enterica typhi bacteria crosses the blood stream
    • Endotoxins act on the vascular and nervous system
  67. What does Mycobacterium cause?
    • M. Tuberculosis
    • M. Leprae
  68. Why is M. Tuberculosis and M. Leprae hard to treat?
    • Distinctive cell wall: outer most layer is not LPS but a waxy water resistant layer
    • Few antimicrobial drugs can enter the cell
  69. Varicella-Zoster virus, what is causes after its latent period?
  70. two or more strains of a virus combine to form a new subtype having a mixture of the surface antigens of the two or more original strains
    Antigenic Shift
  71. changes to the flu virus that happen slowly over time
    Antigenic Drift
  72. What causes tooth decay
    Strep mutans
  73. ingestion of a preformed toxin (botulism)
  74. growth of a pathogen in intestines
  75. What is gastroenteritis?
    inflammation of stomach and intestinal mucosa (diarrhea, dystentery)
  76. What is Campylobacter jejuni?
    • Leading cause of food borne illness in U.S.
    • Caused by INFECTION
    • causes diarrhea
  77. C. Difficile info...
    • Prolonged ABX use
    • Predominately nosocomial
    • Found in healthy adults
  78. Why diseases like gas gangrene and bacterial endocarditis are difficult to treat with antibiotics
    • Endocarditis: immune system response or ABX cannot directly reach the valves via the blood stream
    • GAS gangrene: antibiotics may not penetrate the ischemic tissue
  79. Types of virulence factors and the ways bacteria protect themselves
    • Capsules
    • Toxins
    • Enzymes
    • Colonization
    • Adherence to cells
    • Obtains nutrition from host
  80. ESKAPE +1 organisms; Name them
    • Enterococcus faecium
    • Staphylococcus aureus
    • Klebsiella pneumoniae
    • Acinetobacter baumannii
    • Pseudomonas aeruginosa
    • Enterobacter Species
    • Clostridium deficile
  81. Important things about  Enterococcus faecium
    • Propensity to mutate
    • ABX resistance
    • Produces thicker biofilms
  82. Important things about  Staphylococcus aureus
    • Highly pathogenic due to virulence factors even in healthy patients
    • Biofilms post-implanted medical devices
    • ABX resistance
  83. Important things about  Klebsiella pneumoniae
    • Thick capsule (fimbrial adhesins)
    • ABX resistance
  84. Important things about  Acinetobacter baumannii
    • Environmental persistence – survives on inanimate surface up to 5 months
    • Widening of periplasmic space -> thickening of cell wall
    • Grows at high temps, pH’s, nutrient levels = adaptation
    • Efflux pump (pumps ABX back out of cell)
  85. Important things about  Pseudomonas aeruginosa
    • Resistance to antimicrobials
    • Degrades broad range of organic molecules for nutrition (diesel fuel)
    • Efflux pump
  86. Important things about  Enterobacter Species
    • ICU bug -> causes significant morbidity and mortality
    • Risk factors = hospitalization 2+ weeks, invasive procedures -> 72 hours, ABX last 30 days
  87. Important things about  Clostridium deficile
    • Responsible for 2/3 of all healthcare associated infections
    • #1 catheter associated UTI’s
  88. Why do antibiotics make an infection worse?
    • ABX destroys bacteria
    • Endotoxins/exotoxins linger around
    • Endotoxin causes fever triggering immune response
Card Set
Micro - Lecture Final
Micro - Lecture Final