Immunity Overview – Flashcards

Unlock all answers in this set

Unlock answers
question
What are the two main mechanisms of defenses?
answer
Innate and Adaptive
question
What are your innate defenses considered?
answer
First line of defense. Non-specific and inheritied.
question
What are examples of innate defenses?
answer
1.)Physical barriers
2.)chemical defenses
3.)normal bacterial flora
4.)cell communicators (cytokines)
5.)sensor systems (complements)
6.)Phagocytosis
7.)Fever
question
What are your adaptive defenses considered?
answer
The second line of defense if pathogen overtakes innate. Specific, learned and have memory.
question
What are the two wbc involved with adaptive defenses?
answer
T-lymphocytes and B-lymphocytes
question
What are the 3 types of granulocytes?
answer
1.)Neutrophils
-most abundant
-phagocytes
2.)Basophils
-least numerous
-involved in allergic rxns
3.)Eosinophils
-combat parasitic worm infections
question
What are the 2 types of agranulocytes?
answer
1.)monocytes
2.)lymphocytes
question
What are the 2 cells that a monocyte differentiates into?
answer
1.)macrophage - phagocyte
in liver, spleen, lymph nodes...
2.)dendritic - phagocyte
APC
question
What are the 3 cells that a lymphocyte differentiates into?
answer
1.)t-cells
2.)b-cells
3.)NKC
question
What is a t-cell?
answer
Require APC's.

Four main types
-cytotoxic
-helper t
-suppressor t
-memory t
question
What is a b-cell?
answer
differentiates into -
1.)plasma cell
2.)memory B cell
question
What is a natural killer cell?
answer
NON-SPECIFIC KILLER of cells that have been bound by antibodies or have abnormal traits. use perforins and granzymes to destroy the cells.
question
What are the 2 physical barriers of the body?
answer
1.)Skin
2.)Mucus Membranes
question
The ______ contains tightly woven fibrous connective tissues.
answer
dermis
question
The epidermis possesses a water-repelling protein called _____ which makes the skin an arid environment.
answer
keratin
question
What do mucus membranes line?
answer
digestive, respiratory, and urogenital tracts
question
How does the mucus membrane trap and wash away microbes?
answer
Constantly bathed in fresh mucus and other body secretions.
question
What moves microbes towards body openings where they are more easily eliminated?
answer
Peristalsis & cilia
question
What are 5 chemical defenses?
answer
1.)Lyzozymes
2.)Peroxidase Enzymes
3.)Lactoferrin
4.)Defensins
5.)Changing pH
question
What are lysozymes?
answer
Enzymes that degrade peptidoglycan.
question
Where are lysozymes found?
answer
Body secretions including tears, saliva, mucus, perspiration, tissue fluids, blood, and phagocytic vesicles.
question
What are lysozymes effective against?
answer
Gram POSITIVE bacteria because lack of outermembrane
question
What are peroxidase enzymes?
answer
Break down hydrogen peroxide to produce oxidizing agents. Potent against catalase-negative organisms.
question
Where are peroxidase enzymes found?
answer
saliva, milk, tissue fluids, phagocytic vesicles
question
What is lactoferrin?
answer
an iron-binding protein found in saliva, mucus, and milk.
question
What does lactoferrin make?
answer
Iron
question
What are defensins?
answer
Antimicrobial peptides found in mucus membranes and phagocytic cells.
question
How do defensins work?
answer
Insert themselves into bacterial cell membranes creating pores that disrupt membranes integrity
question
What jucies change pH?
answer
Urine, gastric juices, and vaginal secretions lower pH

Bile RAISES pH
question
What is your normal biota?
answer
Normal growing bacteria on the body surfaces of healthy individuals.
question
What are its 4 fxns?
answer
1.)create competition
2.)some produce antimicrobial agents
3.)may block binding sites
4.)cell communication
question
What are the 2 components of your biota that allows cellular communication?
answer
1.)surface receptors
2.)cytokines
question
What are the surface receptors?
answer
The cell's "ears". Integral membrane proteins that only bind to specific chemicals.
question
What are the cytokines?
answer
the cell's "voice". Released by cells in response to invasion. Bind to surface receptors to initiate a change in that cell.
question
What are 5 important cytokines?
answer
1.)Chemokines - stimulate chemotaxis
2.)Interferons - produced by virus-infected cells
3.)Colony-stimulatiing factors - multiplication and differentiation
4.)INterleukins - function in innate defense, inflammation, adaptive immunity
5.)Tumor necrosis factor - kill tumor cells, inflammatory response, programmed cell death
question
What is the sensor system
answer
Detect the presence of microbial ivasion or tissue damage.
question
What are the two types of sensor system?
answer
1.)Toll-like
2.)Complements
question
What is the toll-like receptor?
answer
Located on the membranes of certain host cells. Detect specific chemicals/structures associated with microorganisms and initiate immune response.
question
What is the complement system?
answer
Series of normally innactive circulating proteins. Increase the activity of antibodies.
question
How many complements are there?
answer
9. C1-C9
question
What are the 3 outcomes that come from the complement system?
answer
1.)inflammation
2.)foreign cell lysis
3.)opsonization
question
What complements cause the inflammatory response?
answer
c3a and c5a increase permeability and act as chemoattractants
question
What complements cause foreign cell lysis?
answer
c5b, c6, c7, c8, c9 aggregate within the membrane creating holes. Gram - most succpetible
question
What complements cause opsonization?
answer
c3b coats the surface of the foreign cell making it sticky and more easily phagocytized
question
What are the steps of phagocytosis?
answer
1.)chemotaxis
2.)adherance
3.)engulfment
4.)phagolysosome formation
5.)destruction and digestion
6.)exocytosis of residual bodies
question
What are residual bodies?
answer
by-products of the destruction of the antigen
question
What is one of the strongest indicators of infectious disease?
answer
A fever
question
What does a fever cause cells to sequester?
answer
zinc
question
What does fever decrease and increase within the pathogen and the host?
answer
decrease bacterial metabolism - increase host's defense responses.
question
What causes a fever?
answer
A pyrogen that acts on the hypothalamus
question
What are the 2 types of pyrogens?
answer
1.)endogenous
2.)exogenous
question
What are endogenous pyrogens?
answer
Produced by the host. Ex: cytokines
question
What are exogenous pyrogens?
answer
Produced by the invading microbe. Ex: bacterial toxin
question
What are 4 characteristics of the adaptive immune system?
answer
1.)antigen-specific
2.)systemic
3.)is learned
4.)has memory
question
What are the 2 types of adaptive immunity?
answer
1.)cell-mediated
2.)antibody-mediated
question
How does cell-mediated immunity work?
answer
An antigen invades the innate defenses, and then that antigen is taken up by an APC and broken down. Fragments of the antigen mix with MHC proteins on the APC's surface and are recognized by the T-cell and becomes activated. Then, then t-cells divide and differentiate.
question
What are cytotoxic t-cells?
answer
CD8 cells. Primarily attack cells infected by viruses or other intracellular microbes, tumor cells and transplanted cells.
question
What does activation of a cytotoxic t-cell result in?
answer
Apoptosis of the target cell
question
We are unaware of how apoptosis occurs but what is speculated?
answer
1.)secretion of preforin and granzymes
2.)secretion of lymphotoxin into the target cell fragmenting its DNA
question
What are helper-t cells?
answer
CD4. DO NOT KILL ANYTHING. Produce a number of interleukins. Stimulate production of other t and b cells.
question
What is the interleukin that stimulates t-cell proliferation?
answer
IL-2
question
What is the interleukin that promotes t-cell growth and production of IgE
answer
IL-4
question
What is the interleukin that promotes secretion of IgA?
answer
IL-5
question
What are the other two cells they divide into?
answer
Supressor T and Memory T
question
When does antibody-mediated immunity occur?
answer
Only after cell-medaited immunity has failed.
question
What happens in antibody-mediated immunity?
answer
Helper t-cells activate the response and stimulate b cells to divide into plasma and memory b cells. The antibody then merges with the antigen and causes a chain of reactions.
question
What happens once the antigen and antibody bind?
answer
1.neutralization
2.immobilization
3.attraction of phagocytes
4.enhances phagocytosis
5.stimulate inflammation
6.inhibit antigen metabolism
question
What are the 5 classes of antibodies?
answer
1.)IgA
2.)IgD
3.)IgE
4.)IgG
5.)IgM
question
What is IgA?
answer
Found in blood plasma, mucus membranes, and breast milk. Prevents pathogens from adhering to epithelia and penetrating tissues.
question
What is IgD?
answer
Integral part of B cell membrane. Acts as an antigen presenter.
question
What is IgE?
answer
Found mainly in tonsils, skin, and mucus membranes. Stimulates mast cells to release contents and attracts eosinophils to parasitic worm infectiosn.
question
What is IgG?
answer
75-85 or circulating antibodies in plasma. Crosses placenta to confer temporary immunity to the fetus.
question
What is IgM?
answer
Found on the B cell membrane and circulating in plasma. Presence indicates recent infection.
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New