| Question | Answer |
| peyer's patches | found in the wall of the sm intestine; capture and destroy bacteria; sentinel of the digestive tracts |
| macrophages | engulf and destroy bacteria, viruses and other foreign substances; found in the lymph nodes; "big eaters" |
| immediate hypersensitivity (acute) | flood of histamine bind to mast cells, blood vessels become dilated and leaky, largely to blame for symptoms of allergy |
| immunosuppressive therapy | medications to prevent organ or tissue rejection |
| pyrogens | chemicals secreted by white blood cells and macrophages exposed to foreign cells or substances in the body |
| innate defense system (non-specific) | responds immediately to protect the body from all foreign substances; mechanical barriers that cover body surfaces, the initial battlefront to protect the body |
| antibodies | immunoglobulins (IG's); the gamma globulin part of blood proteins |
| cytokines | proteins important in the immune response, secreted by macrophages |
| first line of defense | skin and mucous membranes |
| thymus gland | functions at peak levels only during youth, low in throat overlying the heart; produces thymosin, functions in programing of lymphocytes; protective role |
| lymph capillaries | weave between tissue cells and blood capillaries in connective tissues, absorbing leaked fluid, have minivalves; larger particles are allowed to enter |
| trabeculae | strands from the fibrous capsule of the lymph node |
| monoclonal antibodies | used for diagnosing pregnancy, hepatitis, rabies; antibodies prepared commercialy for research and clinical testing |
| allergic contact dermatitis | the reaction to allergens that are touched; the reaction of the TB antigen |
| nonself | foreign |
| lysozyme | enzyme that destroys bacteria |
| tonsils | lymphoid tissue ringing the pharynx; traps and removes any bacteria or foreign pathogens; can become congested with bacteria, becoming tontillitis |
| immunodeficiencies | congenital and acquired conditions in which the production or function of immune cells or complement is abnormal |
| immunity | specific resistance to disease |
| follicles | the collection of lymphocytes found in the lymph node cortex |
| antigen specific | recognizes and acts against particular pathogens or foreign substances |
| neutralization | when antibodies bind to specific sites on bacterial exotoxins, blocking harmful effects of the exotoxin or virus |
| histamine and kinins | inflammatory chemicals that cause blood vessels to dilate and capillaries become leaky, activate pain receptors and attract phagocytes/white blood cells to the area |
| immunology | study of immunity |
| Humoral immunity (antibody-mediated immunity) | provided by antibodies present in the bodys fluids |
| gene determined | determine what specific foreign substances our immune system will be able to recognize and resist |
| delayed hypersensitivities | cytokines released by activated T cells, antihistamines are not helpful; such as contact dermatitis |
| inflammatory response | redness, heat, swelling, pain |
| complete antigens | provoke an immune response and bind with products of that response (antibodies or sensitized lymphocytes) |
| lymph | excess tissue fluid |
| thoracic duct | receives lymph from the rest of the body |
| right lymphatic duct | drains lymph from the right arm and right side of the head and thorax |
| opsonization | cell membrane becomes sticky so they are easier to phagocytize |
| hilum | lymph exits this indented region of the lymph node |
| complement fixation | complement proteins bind to certain sugars or proteins (as in antibodies) on foreign cell surface; vasodilators, chemotaxis chemicals, opsonization |
| antibody structure | 4 amino acids chains linked by disulfide bonds, 2 heavy chains, 2 light chains, half as long as heavy chains |
| cytotoxic (killer) T cells | specialize in killing virus infected, cancer or foreign graft cells; release perforins and granzymes |
| severe combined immunodeficiency disease (SCID) | deficit of both B and T cells, no protection against pathogens of any type (bubble boy) |
| natural killer cells | police the body in blood and lymph, lymphocytes that can lyse and kill cancer cells and virus-infected body cells; act spontaneously against any target by recognizing certain sugars on the intruder's surface; not phagocytic, release perforins |
| interferon | proteins that diffuse to nearby cells and bind to their membrane receptors, stimulating the synthesis of proteins that interere with virus ability to multiply |
| adaptive defense system (specific) | mounts the attack against particular foreign substances; two armed system, humoral arm and cellular arm |
| cellular immunity (cell-mediated immunity) | protective factor is living cells, lymphocytes defend the body directly by lysing the cells or indirectly by releasing chemicals that increase inflammatory response |
| cortex | outer part of the lymph node, contains collections of lymphocyes called follicles |
| precipitation | immobilized antigen molecules |
| autografts | tissue grafts transplanted from one site to another in the same person |
| IgE | secreted by plasma cells in skin, mucosa of gastrointestinal and respiratory tracts, tonsils; binds to mast cells and basophils, tirggers release of histamine |
| attenuated | pathogens in vaccines that are living but extremely weakend |
| edema | fluid that is not transfered back to blood vascular system, impairs the ability of tissue cells to exchanged interstitial fluid with blood |
| lymphatic tissues and organs | house phagocytic cells and lymphocytes, playing essential role in body defense and resistance to disease |
| antimicrobial proteins | attack microorganisms directly or hinder their ability to reproduce; complement proteins and interferon |
| spleen | soft blood-rich organ; filters and cleanses blood of bacteria, viruses and other debris; lymphocyte proliferation; destroys worn-out red blood cells, returning some of breakdown products to liver; restores platelets, blood reservoir; AKA RBC graveyard |
| hapten (incomplete antigen) | the molecule that causes allergies; an attack on our body that is harmful rather than productive |
| allografts | tissue grafts taken from a person other than identical twin |
| xenografts | tissue grafts harvested from a different animal species |
| agglutination | clumping of the foreign cells (as in blood transfusions of incorrect blood type) |
| immune response | nonspecific defenses providing protection that is carefully targeted against specific antigens |
| phagocytes | macrophage or neutrophil engulf a foreign particle; flowing cytoplasmic extensions bind to the particle and pull it inside, closing it in vacuole, fused with lysosome and contents are broken down or digested |
| mucosa | hydorchloric acid and protein-digesting enzymes kill pathogens; sticky mucus traps microorganisms that enter digestive and respiratory passages |
| primary humoral response | clone formation of the antigen |
| lymphatic collecting vessels | the system of capillaries, successively larger until reaching the venous sytem |
| clone | identical cells descended from the same ancestor cell |
| clonal selection | lymphocyte begins to grow and multiplies rapidly to form an army of cells all like itself, bearing same antigen-specific receptors |
| secondary humoral response | more effective and quick, due to memory of primary immune response |
| active immunity | B cells encounter antigens and produce antibodies against them |
| anaphylactic shock | occurs when the allergen directly enters the blood and circulates rapidly thru the body |
| isografts | tissue grafts donated by genetically identical person |
| systemic | immunity is not restricted to initial infection site |
| variable region (V) | the narrower end of the chain forming the antibody |
| constant region (C) | the larger end of the chain forming the antibody |
| plasma cells | daughter cells of the lymphocytes, releasing antibodies |
| lymphoid organs | tonsils, thymus, spleen, peyer's patches; reticular connective tissue; only the lymph node filters lymph |
| passive immunity | B cells are not challenged by the immune response, memory does not occur and temporary protection ends when response degrades |
| memory or memory cells | immune response is remembered and mounts even stronger attacks on previously encountered pathogens |
| regulatory T cells | suppressor T cells; release chemicals that suppress activity of both T and B cells, vital for winding down and stopping immune response |
| lymph nodes | the detour that lymph takes where it is cleansed of debris, examined by cells of the immune system; help protect the body by removing foreign material like bacteria and tumor cells, produce lymphocytes; kidney shaped, less than 1 inch |
| IgD | important in activation of B cell; always attached to B cell |
| diapedesis | the passage of blood cells thru intact vessel walls into the tissues |
| acidic PH | inhibits bacterial growth, containing chemicals that are toxic to bacteria |
| self-antigens | our personal variety of protein molecules; strongly antigenic to other people |
| T lymphocytes (T cells) | non-antibody producing lymphocytes that constitute the cell-mediated arm of adaptive defense system; arise from lymphocytes and migrate to the thymus |
| third line of defense | immune response; indentfying and destroying or inactivating foreign molecules |
| acquired immune deficiency syndrome (AIDS) | most devastating of the acquired immunodeficiences, cripples the immune system by interefering with the activity of helper T cells |
| antigen binding site | the variable regions of the heavy and light chains in the antibody combine to form this site, shaped to fit its specific antigen |
| IgG | most abundant antibody in plasma; main antibody in both primary and secondary rsponse, crosses placenta |
| helper T cells | act as directors or managers of the immune system |
| mucosa-associated lymphatic tissue (MALT) | peyer's patches and tonsils, acting as sentinel to protect upper respiratory and digestive tracts |
| autoimmune diseases | MS, myasthenia gravis, Graves' disease, Type 1 diabetes, SLE, glomerulonephritis, RA |
| antibody function | complement fixation, neutralization, agglutination, precipitation |
| subclavian veins | lymph drains into this vein, one on each side of the body |
| medulla | in the lymph node where phagocytic macrophages are located |
| afferent lymphatic vessels | lymph enters the convex side of a lymph node through these |
| germinal center | the center of the lymph node; shows an increase in activity when antibody production is high |
| antigen | any substance capable of mobilising our immune system and provoking an immune respone |
| lymphocytes | white blood cells, found in the lymph nodes, respond to foreign substances in lymphatic stream |
| antibody classes | IgM, IgA, IgD, IgG, IgE |
| capsule | each node is surrounded by a fibrous capsule |
| second line of defense | cells and chemicals, relying on phagocytes and natural killer cells; fever also |
| efferent lymphatic vessels | lymph drains from the lymph node thru these; connect to the lymph node at the hilum |
| vaccines | artificially aquired immunity |
| lymphatic vessels (lymphatics) | an elaborate drainage system that transports fluids back to the blood vascular systems; flows only toward the heart; thin walled |
| pus | mixture of dead or dying neutrophils, broken-down tissue cells, living and dead pathogens |
| complement proteins | 20 proteins circulating in the blood, inactive until they fix to foreign cells, become activiated and fight foreign cells |
| immune system | innate and adaptive defense systems |
| IgM | attached to B cell; free in plasma; serves as antigen receptor, released during primary respnse; agglutinating agent, fixes complement |
| allergies (hypersensitivities) | abnormaly vigorous immune responses in which immune system causes tissue damage as it fights off threat that would otherwise be harmless to the body |
| chemotaxis | oriented movement toward or away from a chemical stimulus, chemicals in this case being histamine and kinins |
| pathogens | harmful or disease causing microorganisms |
| perforin | a lytic chemical that attacks a cell membrane causing the nucleus to disintegrate |
| lymphatic system | two semi-independent parts: lymphatic vessels and lymphoid tissues and organs; low pressure system; vessels contract rhythmically, pumping the lymph along |
| granzymes | protein digesting enzymes |
| antigen presentation | the process of the "T cell" recognizing self and activating correct response |
| B lymphocytes (B cells) | produce antibodies overseeing humoral immunity; form in the bone marrow |
| IgA | monomer in plasma, dimer in secretions such as saliva, tears, intestinal juice, milk; bathes and protects mucosal surfaces from pathogens |
| sinuses | lymph flows thru these in the lymph node |
| membrane attack complexes (MAC) | produce lesions, complete with holes, in the foreign cell surface, allowing water into the cell, causing it to burst |
