5. The immune system then responds by producing antibodies and specialized lymphocytes. Usually, the immunity is for a long term.
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7. Naturally Acquired Passive Immunity Naturally acquired passive immunity involves the natural transfer of antibodies from a mother to a child. An expectant mother is able to pass some of her antibodies to her fetus across the placenta. In addition, certain antibodies are also passed from the mother to the child during breast feeding. Generally immunity lasts only as long as the antibodies are active usually a few weeks or 6 months.
8. Artificially Acquired Passive Immunity Artificially acquired passive immunity involves an injection of antibodies into the body. These antibodies come from an animal or human who is already immune to the disease.
9. Immunity Overview Immunity: The body's ability to fight off harmful micro-organisms –PATHOGENS- that invade it. The immune system produces antibodies or cells that can deactivate pathogens. Fungi, protozoans, bacteria, and viruses are all potential pathogens. Antigen: Molecules from a pathogen or foreign organism that provoke a specific immune response.
10. The Immune System - includes all parts of the body that help in the recognition and destruction of foreign materials. White blood cells, phagocytes and lymphocytes, bone marrow, lymph nodes, tonsils, thymus, and spleen are all part of the immune system.
11. Function of the immune system Destroy pathogens Detect and kill abnormal cells Remove dead cells and other debris from the body
14. The immune system recognizes, attacks, destroys, and remembers each pathogen that enters the body. It does this by making specialized cells and antibodies that render the pathogens harmless.
15. Unlike the first line and second line defense the immune system differentiates among pathogens.
22. many specific defenses develop after birth upon exposure to an antigen; an antigen can be a pathogen (disease-causing organism), foreign protein (e.g. toxin), abnormal or infected body cell, foreign tissue transplant
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24. Humoral immunity involves the antibodies and the B cells that they secret them; is directed against extracellular pathogens
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26. Immunity is the result of the action of two types lymphocytes, the B lymphocytesand the T lymphocytes. B cells produce antibodies that are secreted into the blood and lymph. T cells attack the cells that have antigens that they recognize.
27. Shared feature of B & T lymphocyte Specificity of receptors: Both B & T lymphocyte have specific receptor for specific antigen Diversity of receptors: There are huge numbers of different lymphocyte each with its own unique antigen receptor Regulation of activation: Activation of B & T cells leads to process clonal expansion Memory: Respond to subsequent exposure to the same antigen
28. Antigen: Self Antigen There are a vast number of antigen outside the body. There are also internal antigen called self antigen. Lymphocyte must recognize antigen from pathogen while ignoring self antigen
29. Antigen receptor- Specificity The surface of mature B & T lymphocyte studded with lymphocyte antigen receptor that allows these cells to identify their particular antigen shape The antigenic specificity of B & T lymphocyte is determined by the shape of their antigen receptor B & T cells have a related structure and similar function, there are differences in their shape and the way they interact with antigen
30. Antigen receptor The B cell antigen receptor is Y-shape antibody molecule and directed against antigen in the extracellular fluid When the antigen occupy the antigen binding site on the B cell receptors, the receptor signals the cell that antigen found
31. Antigen receptor T lymphocyte receptor is not: Membrane bound antibody Y-Shaped T cell directed against the body’s own cells when they are invaded
32. Antigen receptor When antigen bind receptors and activate the receptors, the cell divides and make clone with identical receptor This matching mechanism called clonal selection
33. Humoral (Antibody-Mediated) Immunity Involves production of antibodies against foreign antigens. Antibodies are produced by a subset of lymphocytes called B cells. B cells that are stimulated will actively secrete antibodies and are called plasma cells. Antibodies are found in extracellular fluids (blood plasma, lymph, mucus, etc.) and the surface of B cells. Defense against bacteria, bacterial toxins, and viruses that circulate freely in body fluids, before they enter cells. Also cause certain reactions against transplanted tissue.
