Test Two Text 3

  1. Pathogenicity
    the ability to cause disease by overcoming the defenses of a host, and virulence is the degree or extent of pathogenicity 
  2. a.       How Microorganisms enter a host
                                                                   i.      Pathogens must __ to cause disease. But, sometimes, disease is caused by the __. Pathgens gain entrance through several avenues, called __
    1.       __(7)__
    • gain access to host
    • accumulation of microbial waste products
    • portals of entry

    Mucous membranes lining the respiratory tact, GI tract, genitourinary tract, conjunctiva, membrane that covers eyeballs and eylids
  3. a.       _______ is easiest through ___
    b.      GI track can be infected due to __, __, and __; can be destroyed by __ and __ in stomach or by __ and __ in small intestine
                                                                                                                                           i.      Those that survive do what?
    c.       Genitourinary tract: __
    • Respiratory tract
    • inhalation
    • food, water, and dirty fingers
    • HCl and enzymes
    • by bile and enzymes
    • cause disease
    • sexual contraction; STIs
  4. 1.       Skin: __ is impenetrable, but __allow entry
    2.       Parenteral route: __
    Can be caused by punctures, injections, bites, cuts, wouns, etc
    • unbroken skin
    • openings like hair follicles 
    • occurs when microbes are deposited directly into the tissues beneath the skin or into mucous memrbaens when these barriers are penetrated or injured
  5.                                                                i.      The Preferred portal of entry
    1.       Occurrence of disease depends on several factors, only one of which is the __
    2.       Many pathogens have a __ that is a prerequisite to their being able to cause disease
    a.       If they gain access by another portal, __
    • portal of entry
    • preferred portal of entry
    • disease might not occur
  6.                                                                i.      Numbers of Invading Microbes
    1.       Likelihood of diseases increases as the __ increases
    2.       Virulence of microbe is expressed as __
    3.       Potency of a toxin is __
    • number of pathogen
    • ID50 (infectious dose for 50% of a sample population)
    • LD50
  7.                                                                i.      Adherence
    1.       For most pathogens, attachment, called __(adhesion) is necessary in __; and, it is accomplished by __ or __ that bind specifically to __ on the cells of certain __
    • adherence 
    • pathogenicity
    • adhesins or ligands
    • complementary surface receptors
    • host tissues
  8. a.       __may be located on the __, __, __, or __
                                                                                                                                           i.      They are usually __ and __
                                                                                                                                         ii.      Different strains can vary in __; different cells of the same host can vary as well
    2.       If adherence is affected, __
    3.       Microbes can also __to one another, creating __, which allows them to __ and __; they resist __ and __
    • Adhesins 
    • glycocalyx or pili, fimbriae, and flagella
    • glycoproteins and lipoproteins
    • adhesion structure
    • infection is usually prevented
    • adhere 
    • biofilms
    • share nutrients and prevent dehydration
    • disinfectants and antibiotics
  9. a.       How Bacterial Pathogens Penetrate Host Defenses
                                                                   i.      __increase virulence of species and __ by __ due to inability to __
    1.       __can be produced against the __to be destroyed
                                                                 ii.      Cell wall components have chemical substances that contribute to __
    • Capsules 
    • resists host defenses
    • impairing phagocytosis
    • adhere to bacterium
    • Antibodies 
    • capsule 
    • virulence
  10. 1.       Ex: __, which is found on cell surface and fimbriae
    a.       The M protein __
    2.       Some bacteria have __and an outer membrane protein called __to attach to host cells
    a.       Following attachment by both __and __, the host cells take in the bacteria
    • M protein
    • mediates attachment of the bacterium to epithelial cells of the host and helps the bacterium resist phagocytosis by WBCs

    • fimbriae 
    • Opa 
    • Opa 
    • fimbriae
  11. a.       __ that makes up the cell wall can also increase virulence by __, and can even __
    • Waxy lipid
    • resisting digestion by phagocytes
    • multiply inside phagocytes
  12.                                                                i.      Enzymes can be produced by bacteria to __ and __; these are __
    1.       Coagulases are __
    a.       __is usually converted into __by __, the threads that form a blood clot. With this __, bacteria ca be protected from __
    • digest materials between cells
    • form or digest blood clots
    • exoenzymes
    • bacterial enzymes that clot the fibrinogen in blood

    • Fibrinogen 
    • fibrin 
    • coagulases
    • fibrin clot
    • phagocytosis
  13. 1.       Kinases are bacterial enzymes that do what?
    2.       Hyaluronidase does what?
    a.       Involved in __ and allowing microbe spread
    • break down fibrin and digest clots formed by the body to isolate the infection
    • hydrolyzes hyaluronic acid, a type of polysaccharide that holds together certain cells of the body, particularly cells in connective tissue
    • tissue blacking of infected wounds
  14. 1.       Collagenase does what?
    2.       __ can be produced by pathogens to destroy antibodies
    facilitates spread of gas gangrene by breaking down collagen, which forms the connective tissue of muscles and other body organs and tissues

    IgA proteases
  15.                                                                i.      Antigenic variation
    1.       In the presence of antigens, the body __, which __ and __. But, some pathogens can __, called __ so as to be unaffected
    • produces proteins called antibodies
    • bind to the antigens and inactive or destroy them
    • alter their surface antigens
    • antigenic variation
  16.                                                                i.      Penetration into the Host Cell Cytoskeleton
    1.       Interaction of attachment triggers signals in the host cell that activates factors that result in __
    a.       Ex: actin and other ECM proteins can __ to __
    • entrance of bacteria
    • rearrange to allow entry
  17. a.       How Bacterial Pathogens Damage Host Cells
                                                                   i.      If pathogen overcomes host defense, damage can be done by __, __, by __, and by __
    • using the host’s nutrients
    • causing direct damage to immediate vicinity of invasion
    • producing toxins
    • inducing hypersensitivity reactions
  18.                                                                i.      Using Host’s Nutrients
    1.       Bacteria need __; and, since human iron count is low, pathogens secrete proteins called __, which do what?
    2.       Other pathogens have receptors that do what?
    3.       Some bacteria do what when iron levels are low, which causes what?
    • iron
    • siderophores
    • take iron away from iron-transport proteins
    • bind directly to iron-transport protiens and hemoglobin
    • produce toxins
    • killing host cells and releasing their iron to make it available to bacteria
  19. Direct Damage
    1.       As pathogens metabolize and multiply in cells, the cells __, which can cause what to happen?
    2.       Some bacteria also penetrate host cells by __ and __
    • rupture
    • the pathogens to be released which spread to other tissues in greater numbers and disupt host cells by a reverse phagocytosis process
    • excreting enzymes and by their own mobility
  20. 1.       The capacity of microorganisms to produce toxins is __; __refers to the presence of toxins in the blood
    2.       Exotoxins: __
    • toxigenicity
    • toxemia 

    produced inside bacteria as part of their growth and metabolism and are secreted following lysis; they are proteins, and many are proteins that catalyze only certain biochemical reactions
  21. a.       Genes for them are on __ or __
    b.      They are __and can easily __
    c.       How do they work?
    d.      Highly specific and among the most lethal
    e.      It is the exotoxin that does what, making them what?
    f.        Immunity against exotoxins is __
                                                                                                                                           i.      When exotoxins are inactivated by heat or chemicals, they can’t __ but they do __; such altered exotoxins are called __
    • plasmids or phages
    • soluble 
    • diffuse into the blood
    • Work by destroying particular parts of the host’s cells or by inhibiting certain metabolic functions

    • produces the specific signs and symptoms of the disease, making them disease specific
    • antitoxins 

    • cause the disease
    • allow antitoxins to develop
    • toxoids
  22. a.       Types include
                                                                                                                                           i.      __

    A-B toxins, A being the active (enzyme) component, and B being the binding component

    Membrane-disrupting toxins contribute to virulence by killing host cells and aiding the escape of bacteria from sacs within phagocytes into host cytoplasm

    Superantigens provoke a very intense immune response and are bacterial proteins
  23. 1.       A-B toxin is released from __. B component does what? The plasma membrane __at point where contact is made, and the exotoxin enters the cell by __. The__ and __are enclosed in a vesicle. The A-B components do what? 

    What does A do? What does B do?
    • bacteria
    • attaches to receptor
    • invaginates 
    • receptor-mediated endocytosis

    •  A-B exotoxin
    • receptor
    • separate

    A alters the function of the host cell, often by inhibiting protein synthesis

    B is released from host cell, and receptor is inserted into plasma membrane for reuse
  24. Membrane-disrupting toxins contribute to virulence by __ and __
    1.       Cause __of host cells by __ by __
    2.       __kill leukocytes, decreasing __
    3.       __destroy erythrocites
    a.       Those produced by streptococci are __
    killing host cells and aiding the escape of bacteria from sacs within phagocytes into host cytoplasm

    • lysis 
    • disrupting their plasma membranes
    • forming protein channels or disrupting phospholipids

    • Leukocidins 
    • host resistance

    • Hemolysins 
    • stretolysins
  25. __provoke a very intense immune response and are __ 
    1.       Stimulate __ that release a lot of __, which __ and __
    a.       This induces __(6)__
    • Superantigens 
    • bacterial proteins
    • proliferation of T cells
    • cytokines
    • regulate immune responses and mediate cell-to-cell communication
    • fever, nausea, vomiting, diarrhea, shock, and death
  26. 1.       Endotoxins
    a.       What are they?
    b.      When are they released?
    c.       Antibiotics can __, releasing the endotoxin and worsening symptoms
    Part of the outer portion of the cell wall of gram-negative bacteria called lipid A, which is the lipid portion of LPS

    Released when gram-negative bacteria die and their cell walls undergo lysis, thus liberating the endotoxin

    lyse the bacterial cells
  27. a.       They stimulate __to release __at high concentrations, making it toxic
    b.      All endotoxins produce __; can also cause __
    c.       Also activate __, causing the formation of __, which __, leading to death of tissues (DIC)
    • macrophages
    • cytokines 
    • the same signs and symptoms, which include chills, fever, weakness, aches, and shock or death
    • miscarriage
    • blood clotting proteins
    • small blood clots
    • obstruct capillaries
  28. a.       Process:
      i.      Gram negative bacteria are __ and __, releasing __, causing macrophages to produce __. The __are carried via the blood to the __, which releases lipids, called __-->fever)
    • ingested by phagocytes and degraded
    • LPS
    • cytokines (interleukin-a and tumor necrosis factor alpha)
    • cytokines 

    • hypothalamus
    • prostaglandins
  29. a.       Shock caused by bacteria is __
    b.      Gram negative cause __ and is related to __
                                                                                                                                           i.      One effect of TNF release is __; as permeability increases, what happens?
    c.       __usually enhance effects
    • septic shock
    • endotoxic shock
    • secretion of cytokine release by macrophages
    • damage to blood capillaries
    • they lose large amounts of fluid and a drop in blood pressure--> shock , which affects other organs
    • Antibodies
  30. 1.       Plasmids, Lysogeny, and Pathogenicity
    a.       __ are a group of plasmids responsible for resistance of some microbes to antibiotics; may carry info that determines __
    • Resistance factors
    • microbe’s pathogenicity
  31. a.       What is lysogeny?
                                                                                                                                           i.      Such a change in the characteristics of a microbe due to a prophage is called __, in which the bacterial cell is immune to infection by the same type of phage
    Lysogeny is when DNA is incorporated into a bacterial chromosome, becoming a prophage, and remaining latent

    lysogenic conversion
Card Set
Test Two Text 3
Test Two