patho exam 3 part1

Card Set Information

patho exam 3 part1
2015-10-14 13:18:29
exam 3 - 10/7&10/12
Show Answers:

  1. Where are mucosal surfaces washed by fluids?
    -in the mouth, small intestine, and bladder.
  2. Many pathogens have mechanisms of attaching themselves to host ______________.
    epithelial cells
  3. Specific receptors infect _______ parts of the body.
  4. human strains of a particular bacterial species may NOT adhere to __________ cells of an animal and vice versa.
  5. What is required to get to any structure in the first place?
  6. What are specialized structures that provide motility?
    • Flagella 
    • -Fimbriae / Pilli also involved in motility
  7. What is chemotaxis?
    -directed movement of an organism toward (+) or away from (-) a chemical gradient.
  8. Flagellum have the same basic structure between _____________ & __________.
    Bacteria & Archaea
  9. peritrichous flagella
    flagellum all around the flagella
  10. polar flagella
    one flagellum at one end
  11. lophotrichous flagella
    several flagellums at one end
  12. How do peritrichously and lophotrichous flagellated organisms move?
    move in a slow, straight line
  13. some bacteria can move at ___ cell lengths/sec.

    (cheetah - 25 lengths/sec)
  14. polar flagellated organisms move in a .....
    rapid, spinning motion
  15. How many genes are involved in movement of flagellas?
    40 genes
  16. What genes are involved in movement of flagellas?
    regulation genes (synthesis and control)

    structural proteins (makeup the flagella itself)

    chaperone proteins (mediate export of flagella proteins thru cytoplasmic membrane to outside of cell to construct flagellum itself)
  17. What are regulation genes?
    for synthesis and control
  18. Structural proteins are...
    • proteins that help movement of flagella.
    • These proteins make up the flagella itself.
  19. Chaperones proteins mediate...
    export of flagella proteins thru cytoplasmic membrane to outside of cell to construct the flagellum itself.
  20. Flagella consists of several components:
    base & filament
  21. Several "rings" make the ____ body. (Gram (-))

    an outer L in LPS, P in peptidoglycan, MS and C rings are located in Cytoplasmic Membrane and Cytoplasm.
  22. What does the flagella lack?
    -lack outer membrane so no outer L ring. (Gram(+))
  23. What is located at the base that rotates the flagella that is anchored in the cytoplasmic membrane and cell wall?
  24. What acts as motors that switch (reverse) mechanisms that are anchored in the cytoplasmic membrane?
    Mot and Fli
  25. Motion from the basal body uses ____________ Force.
    Proton Motive Force; protons across cytoplasmic membrane thru Mot complex (1000-1200 ions per revolution)         
  26. Smooth "runs" means....
    swimming forward
  27. "tumbles" means...
    cell stops and jigs about, changes direction then "runs" in a new direction
  28. in a gradient, fewer '______' and more 'runs' and bacteria moves attractant or way from a repellant.
  29. Anticlockwise = _____________
    forward motion
  30. clockwise = ____________________
    bundle of flagella pushes apart
  31. forward motion cease and cells _________.
  32. How do polar flagellated cells move?
    reverse direction of rotation results in backwards motion
  33. what are chemoreceptors?
    sensory proteins in the cytoplasmic membrane sense the chemical gradients.
  34. Ahesion .... 

    Surface structures involved in
    • Fibriae 
    • Pilli
    • Capsules
    • Slime Layers
    • Specialized Proteins
  35. What do Fimbriae and Pili have in common?
    rod shaped protein structures
  36. What are the differences of Fimbriae and Pili?
    -differ in thickness and length (often on Gram (-) organisms)

    Fimbriae tends to be used for shorter, thinner structures

    Pili used for longer thicker structures.
  37. Pili are used for....
    longer thicker structures
  38. Fimbriae tends to be used for....
    shorter, thinner structures
  39. How is a cylindrical structure formed?
    -an orderly array of single subunits aka pilin packed in a helical way
  40. How does the pili make contact ? (2-step progress)
    retract and "pull" bacterial close to host cell where adhesins take over and pili depolymerize.
  41. Signal Transduction of pili envokes what?
    attachment of pili envokes a whole range of "gene switching" of virulence genes .
  42. what are ushers ?
    add'l proteins that interact with chaperones and guide the subunits (pili) to cell surface.
  43. What is the chaperone-usher system?
    -present in periplasm, prevent pilus from folding into their final configuration until ready to be extruded from outer membrane
  44. What signals the end of the extrusion process?
    -a periplasmic protein (H)
  45. Assembly of pili is undertaken in what space?
    periplasmic space
  46. What are the functions of Fimbriae / pili ?
    twitching motility. Rapid extension/retraction enables cell to "Crawl" along surface.

    key colonization factor in Neisseria menigitidis (bacterial meningitis) and Vibrio cholerae (cholera)

    avoid host defenses. Pili break easily and when bound by host antibodies can break away (E,F and G proteins). Once body recognizes pili another type of pili w/ diff tip is produced by bacteria.
  47. What is twitching motility?
    rapid extension/retraction enables cell to "crawl" along surface.
  48. What are key colonization factors?
    Neisseria meningitidis (bacterial mengiditis)

    Vibrio cholerae (cholera)
  49. How does the function that avoid host defenses work?
    Pili break easily and when bound by host antibodies can break away (E,F and G proteins). Once the body recognizes the pili another type of pili with a different tip is produced by the bacteria.
  50. List of Pili (Fimbriae) of Gram + bacteria

    structure:(short,thin,rod-like fimbriae)
    • Strep. salvivarius
    • Strep. gordonii
    • Strep. oralis
    • Corynebacterium
    • Actinomyces naeslundii
    • Strep. parasanguis
  51. Strep. salvivarius, Strep. gordonii, Step. oralis, Corynebacterium, Actinomyces naeslundii and Strep. parasanguis are lists of .... ?
    pili (fimbriae) that are oral strains able to adhere to form biofilms.

    -covalent attachment of subunits to each other and to peptidoglycan cell wall.
  52. Strep. salvivarius, Strep. gordonii, Step. oralis, Corynebacterium, Actinomyces naeslundii and Strep. parasanguis morphology...
    short,thin,rod-like fimbriae
  53. Many prokaryotes secrete a loose, unstructured network of polysaccharide / protein-carbohydrate that may be .... ?
    rigid (capsule) or flexible (slime), thick or thin
  54. What are biofilms important for?
    important in pre-infection and establishing colonization/disease. 

    examples: Pseudomonas aeruginosa in Cystic Fibrosis

    Legionella pneumophilia in Legionnaire's disease

    Streptococcus, Bacteroides, Fusobacterium in Dental Plaque (endocarditis)

    S. epidermidis, Enterococcus faecalis, E. coli, Proteus mirabilis, P. aeruginosa, K. pneumoniae -medical catheters
  55. What are biofilms?
    -matrices of organisms where gradients of nutrients exist.
  56. Most Frequent Entry Portals


    ⇢Respiratory tract 

    ⇢Genitourinary tract 

    and many others...
  57. What are preferred portals?
    specific places for microbes to cause disease

    ex: Vibrio cholera infects the GI tract therefore, rubbing an infected oyster on a wound of the skin will not cause cholera.
  58. Tick, mouse, deer interactions -Borrelia burgdoferi -Lyme Disease is an example of ?
    penetration of skin or epithelial layer
  59. Parenteral

    microorganisms are deposited into tissues below skin mucous membranes.....





    splitting of skin due to swelling or dryness.
  60. What happens first for infections?
    enter the body:

    -penetration of skin 

    -penetration of epithelial and mucin layers
  61. What are Rickettsial Diseases ?
    small bacteria, strictly obligate intracellular in vertebrates and have life-cycle associated with fleas, lice or ticks.
  62. Rickettsia prowazekii causes ... ?
  63. Bite of louse punctures skin, makes a trough, blood pools (pool feeding) and bacterium enters from louse fecal matter, which is aided by what?
  64. In Neisseria gonorrhoeae (STD), how does it attach to urogenital epithelia more tightly than other tissues?
    via a protein Opa (opacity associated protein) that binds specifically to the protein CD66 (only found in human epi. cells)
  65. What is mucin?
    network of protein and polysaccharide
  66. What does mucin do?
    • prevent bacteria reaching mucosal cells 
    • GI and vaginal tracts act as lubricants - Goblet cells 
    • respiratory tract - ciliated cells expel bacteria caught in mucin
  67. Some bacteria can actively __________ mucin as a nutrient.