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Flashcards in 19 - Defense Deck (50)

What are the first lines of defense  and give examples of each


  1. Mechanical: skin, mucus, hair, silica, mucosa mb, caughing, sneezing, sweat, urine
  2. Chemical: pH, sweat, earwax, stomach acid, pH - skin, lysosome saliva


The second line of defense is mounted on a cellular levels - name some of the white blood cells and give descriptions


  1. Neutrophil - phagocitic, most neumerous
  2. Macrophage - cleanup team
  3. Natural Killer Cell - kiss bacteria, cancer cells, transplaned cells
  4. Eosinophil - kills parasites
  5. Basophil/Mast cells - produces histamine, aid w/ other wbc


What are some of the indications of inflammation and how are those presnted on a cellular level?


  1. Redness - capillary widening, and increased capillary permeability -> attraction of white blood cells
  2. increased temperature - systemic response to increase communitation within host
  3. Swollen - capillary widening, and increased capillary permeability -> attraction of white blood cells
  4. pain - awareness of inflammation


What does the release of interleukin cause?



  1. the hypothalamus to reste the temp set poin to increase body temp
  2. inhibits microrganisim growth increased WBC production, sequestering more Fe; therefore prevents bacteria from reporducing


Causes us to feel lousy -> rest


When our skin is punctured and bacteria gain entry into the body, what happens?


chemokines are released by macrophages to indicate the injury -> send backup

histamines released by mast cells -> increase permeability of blood vessels - > allowing access by othe leukocytes


____________ is a message spread like a cloud throughout the body to warn the body that antigen has invaded a cell.

How does the boday respond



her cells procuce antivial proteins that bind down antigen so that it can`t replicate


As a result  of receiving an interferon message, what will a cell do to prepare itself for a potential incoming antigen?


creates antiviral proteins that will bind down any antigens preventing the invated from replicating


list the phagocytic cells of the immun system


  • B cells
  • T- Cells
    • THelper
    • T cytotoxic


Non specific immunity: on the molecular scale, what are some of the complmentary proteins that supports the body?



  • inflammation
  • opsonisation - protein tagging the invader to make it easier for the phagocyte to grab onto
  • membrane attack complex (MAC) - creates pores in the invaters cell wall which then allows the flow of water into the hypertone cell  - cell death


What are the two classes of cells that are specific to immunity?


What is another name for them


  • B cells
  • T cells
    • T killer
    • T helper




___________ is called cell-mediated immunity, and  _____ immunity is called antibody mediated immunity or humoral immunity.


T cell

B cell


List antigens


  • viruses
  • bacteria
  • proists
  • fungi
  • animal kingdom
  • others: cance, diff blood type, allergen, organ transplant



Anitgens ahve a non specific respnse to T-cells



What are the three main categories of T cell


  • T helper
  • T cytotoxic cells
  • T suppressor


What are major histocompatibility antigens (MHC)?



  • glycoproteins on surface of body cells except RBC
  • unique to each persone except idential twins
  • have either one or a combo of MHC I & MHC II


In which cells of the body are MHC's not found




On what kind of cell would you find MCH-I?

ont he surface of all body cells except RBC - invloved in activating T cytotoxic cells


Where would you find MHC-II's


on the surface of antigen presenting cells (APC)

  • macrphages, dendritic cells, and B cells
  • activation support of T Helper cells
  • found in at any enterance to the body


__________ are  invloved in giving help to other specific immune cells


T Helper


An antigen presenting cell will _________ an Ag, break it into fragments then presend that Ag fragment together with ___________ to the _________ cell.




T helper


What are the two things that a T-Helper cell needs to signal a response?


  1. interaction with Ag-MHC-II comples
  2. stimulation by a cytokine interleukin



What happens after a T helper cell has been activated?


proliferated into clones and differentiates to become:

  1.   T Helper cell - secreted interleukins to activate B & T cytotoxic cells
  2. T Helper memory cells


What is the advantage to having T helper memory cells?


if the invater returns, = much faster secondary immne response

still "virgin" cell


Do T helper cell kill cells?



they cativate B Cells and T cytotoxic cells

the general


When an individual is infected by HIV what is going on here?


The T helper cells are infected - generals taken out - the army becomes depleated, B cells and Tc cell activation not happening causing secondary illness


C cytotoxic cells are directed towards body cells that are _________.




Cancer cells, virus or fungi infected


What must be in place to activate a Tc cell?


interaction with Ag + MHC-I

cytokine IL from THelper


Once a Tc has been activated, what are the next steps


Proliferation into clones


Differentiation to become either Tc clone cell or a Tc memory cell


Once a Tc clone cell has become active, what does it do now?


Causes self cell death to abnormal cells displaying this specific Ag via

  1. release of perforin - creades holes in cell mb = cell death
  2. release toxdin Lymphotoxin - causes DNA in abnormal cell to fragment = cell death


What is the advantage of the Tc memory cells?


ready to go once the same Ag presents again


What stops this whole cascade of events from spiraling out of control?


Regulatory T cells - communicates "slow down, we're safe"


Which kind of immune cell acts against extracellular antigens


B cells


B cells have ______ on the surface of the cells specific to a ________





What does a B cell require in order to become activated?


  1. the interaction of the MHC-II & antigen
  2. Interleukin from B cell, & IL from T Helper


once conditions are correct, the B cell ahs interacted with the MHC-II & Ag, plus IL communication b/t THelper and B cell, what are the next steps and outcomes?

Proliferation and differentiation

  1. Plasma memory cells = fast 2nd dary response
  2. b/c plasma cells which then secretes antibodies (Ab) or also known as immunoglobulins (ig) that bind down Ag = inactive and ready for macrophages


Specific immunitey requires which kind of cells?


B cells

T cells


What activates an inactive lymphocyte?


  • interaction with their Ag
  • cytokine stimulation b//t cell mb proteins


what are the active B cells called


plasma cells


List some of the ways that an individual acn acquire immunity


  1. active
    • natural - getting sick
    • artificial - vaccination
  2. passive
    • natural - breast milk, blood placenta barrier
    • artificial - antibody infustion - antivenom


One function of antibodies is to
Select one:

A. Deactivate the complement system
B. Neutralize natural killer cells
C. Clump bacteria and viruses for easy phagocytosis by macrophages
D. Eliminate the chance for a secondary response
E. Kill viruses inside of cells

Clump bacteria and viruses for easy phagocytosis by macrophages


Cells that process foreign proteins and complex them with their MHC proteins are called

Select one:
A. Cytotoxic T cells
B. Plasma cells
C. NK cells
D. Antigen presenting cells
E. Helper T cells

Antigen presenting cells


Place the following steps of recognition of an antigen in the order in which they would occur:

1. bacteria degraded

2. dendritic cell engulfs bacteria

3. T cells activated

4. Antigens bind to class II MHC proteins

5. Plasma cells and memory cells produced


Select one or more:
A. 5, 4, 3, 2, 1
B. 4, 3, 1, 2, 5
C. 3, 2, 1, 4, 5
D. 1, 2, 3, 4, 5
E. 2, 1, 4, 3, 5

2, 1, 4, 3, 5


Components of the inflammatory response include all EXCEPT
Select one:

A. Macrophages
B. Neutrophils
C. B cells
D. Mast cells
E. Eosinophils

B Cells


A major difference between the activation of B cells and T cells is that
Select one:

A. T cells must interact with antigens bound to plasma membranes
B. B cells only interact with free antigens
C. B cells are not regulated by helper T cells
D. T cells produce antibodies
E. None of the above

T cells must interact with antigens bound to plasma membranes


How do B cells and Tc cells differ in their response to invaders?
Select one:
A. B cells confer active immunity; Tc cells confer passive immunity
B. B cells release Ab to attack; Tc cells release chemicals
C. B cells engage in the primary response, Tc cells engage in the secondary response
D. B cells are involved in cell-mediated immunity; Tc cells are involved in humoral immunity

B cells release Ab to attack; Tc cells release chemicals


Which of the following is NOT part of the body'€™s non-specific defense?

Select one:
A. complement
B. inflammation
C. T cell
D. interferon
E. macrophage

T Cell


Mary had a baby, whom she breast feeds. What type of immunity would the baby receive from her mother’s milk?
Select one:
A. active, natural immunity
B. active, artificial immunity
C. passive, natural immunity
D. passive, artificial immunity
E. none. Breast milk provides nutrition, not immunity.

passive, natural immunity


Which of the following pertains to a boy who has just inhaled an allergen (pollen) to which he has not developed immunity?
Select one:
A. lgE antibodies will degranulate mast cells
B. lgA in his respiratory secretions will inactivate the allergen
C. IFN will be released by infected cells
D. specific immune response will begin once the allergen is encountered by lymphocytes

specific immune response will begin once the allergen is encountered by lymphocytes


__________ makes bacteria easier for phagocytic cells to grab ahold of - tages them with compliment proteins = sticky