Immunity Overview – Flashcards
Unlock all answers in this set
Unlock answersquestion
| 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. |
