 | Term | Definition |
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Nonspecific Defenses |
Nonspecific External Barrier --> Skin/Mucous Membranes, Nonspecific Internal Defenses --> Phagocytic and natural killer cells /Inflammation/Fever |
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Nonspecific external barriers |
The skin and its secretions block entry and provide an inhospitable environment for microbial growth. Antimicrobial secretions, mucus, and ciliary actions defend the mucous membranes against microbes. |
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Skin |
Prevents microbes from coming in contact with the nutrients that it needs, is an extremely effective barrier against microbial invasion. |
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Mucus membranes |
Secretes lysozymes that destroy bacterial cell walls. The mucus found here also physically traps microboes that enter the body through the nose or mouth. |
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Secretions |
sweat, oil, wax, used in the nonspecific external barrier |
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Nonspecific internal defenses |
White blood cells => macrophages, natural killer cells |
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Cellular defenses |
Phagocytosis, natural killer cells |
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Phagocytic cells |
Ingests and and destroys foreign matter |
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Macrophages |
A type of white blood cell that engulfs microbes and destroys them by phagocytosis; also presents microbial antigens to T cells, helping stimulatre the immune response |
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Neutrophils |
A type of white blood cell that engulfs invading microbes and contributes to the nonspecific defenses of the body against disease. |
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Natural Killer cells |
a type of white blood cell that destroy some virus-infected cells and cancerous cells on contact; part of the immune system's nonspecific internal defense against disease. |
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Chemical defenses |
Complement system, cytokines |
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Complement system |
A series of reactions in which complement proteins bind to antibody stems, attracting to the site phagocytic white blood cells that destroy the invading cell that triggers the reactions. |
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Cytokines |
Any of several chemical messenger molecules released by cells that facilitate communication with other cells and transfer signals within and between the carious systems of the body. They are important in cellular differentiation and the immune system. |
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Inflammatory response |
a nonspecific, local reponse to injury to the body, characterized bu the phagocytosis of foreign substances and tissue debris by white blood cells and by the walling off of the injury site by the clotting of fluids that escape from nearby blood vessels. |
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Mast cells |
Connective tissue cells. They release histamine into the wounded area. |
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Histamine |
A substance released by certaincells in reponse to tissue damage and invasion of the body by foreign substances; promotes the dilation of arterioles and the leakiness of capillaries and triggers some of the events of the inflammatory response. |
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Fever |
An elevation in body temperature caused by chemicals (pyrogens) that are released by white blood cells in reponse to infection. |
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Specific defenses |
Acquired or Adaptive immunity -> lymphocytes |
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Acquired defenses |
lymphocytes produce an immunity after an infection |
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Antigen |
A complex molecule, normally a protein or polysaccharide, that stimulates the production of a specific antibody. |
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Helper T-cells |
A type of T cell that helps other immune cells recognize and act against antigens. |
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Clonal selection |
the mechanism by which the immune response gains specificity; an invading antigen elicits a response from only a few lymphocytes, which proliferate to form a clone of cells that attack only the specific antigen that stimulated their production. |
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Humoral immune response |
an immune response in which foreign substances are inactivated or destroyed by antibodies that circulate in the blood. |
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B-cells |
A type of lymphocyte that participates in humoral immunity; gives rise to plasma cells, which secrete antibodies into the circulatory system, and to memory cells. |
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Antibody |
A protein, produced by cells of the immune system, that combines with a specific antigen and normally facilitates the destruction of the antigen. |
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B-cells recognize |
Antigens |
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Plasma cells |
An antibody-secreting descendant of a B cell. |
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Memory B-cells |
A type of white blood cell that is produced as a result of the binding of an antibody on a B cell to an antigen on an invading microorganism. They persist in the bloodstream and provide future immunity to invaders bearing that antigen. |
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Memory T-cells |
A type of white blood cell that is produced as a result of the binding of a receptor on a T-cell to an antigen on an invading microorganism. They persist in the bloodstream and provide future immunity to invaders bearing that antigen. |
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Cell mediated immune response |
an immune response in which foreign cells or substances are destroyed by contact with T-cells |
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T-cells |
A type of lymphocyte that recognizes and destroys specific foreign cells or substances or that regulates other cells of the immune system. |
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T-cell receptor (TCR) |
A protein receptor, located on the surface or a T cell, that binds a specific antigen and triggers the immune response of the T cell. |
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T-cells recognize |
Infected body cells |
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Cytotoxic T-cells |
a type of T cell that, upon contacting foreign cells, directly destroys them. |
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Immunity |
a state of having sufficient biological defenses to avoid infection, disease, or other unwanted biological invasion. |
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Memory cells |
Cells that can attack specific antigens of infected body cells |
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Pathogens |
a biological agent that causes disease or illness to its host. |
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Virus |
a noncellular parasite particle that consists of a protein coat surrounding a strand of genetic material; multiplies only within a cell of a living organism (the host) |
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Bacteria |
One of life's three domains: consists of prokaryotes that are only distantly related to members of the domain Archaea. |
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Protist |
A eukaryotic organism that is not a plant, animal, or fungus. The term encompasses a diverse array of organisms and does not represent a monophyletic group. |
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Fungi |
a kingdom of eukaryotic organisms. They are heterotrophic and digest their food externally, absorbing nutrient molecules into their cells. Yeasts, molds, and mushrooms are examples. |
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Infection |
the detrimental colonization of a host organism by a foreign species. |
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Infectious disease |
a clinically evident disease of humans or animals that damages or injures the host so as to impair host function, and results from the presence and activity of one or more pathogenic microbial agents, including viruses, bacteria, fungi, protozoa, multicellular parasites, and aberrant proteins known as prions. |
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Sporadic |
Occuring infrequently throughout a population |
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Endemic |
infection is maintained in the population without the need for external inputs |
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Epidemic |
a disease that appears as new cases in a given human population, during a given period, at a rate that substantially exceeds what is "expected", based on recent experience |
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Pandemic |
is an epidemic (an outbreak of an infectious disease) that spreads across a large region (for example a continent), or even worldwide. |
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Routes of Transmission |
Contact transmission, airborne transmission, vehicle transmission, and vector transmission |
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Contact transmission |
touching an infected person, including sexual contact |
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Airborne transmission |
if the microorganism can remain in the air for long periods |
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Vehicle transmission |
applies to microorganisms transmitted to the host by contaminated items such as food, water, medications, devices, and equipment. |
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Vector transmission |
carried by insects or other animals |
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Prevention and treatment |
Prevent transmission, antibiotics, antifungals, vaccination |
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Vaccination |
an injection into the body that contains antigens characteristic of a particular disease organism and the stimulates an immune response |
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Vaccine |
Killed or innactive, weakened, subunit |
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Allergies |
in inflammatory response produced by the body in response to invasion by foreign materials, such as pollen, that are themselves harmless |
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Allergens |
Anything that can upset an allergy |
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Autoimmune disorder |
a disorder in which the immune system produces antibodies against the body's own cells. |
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Autoantibodies |
Attack the body's own cells, tissues, and/or organs, causing inflammation and damage. |
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Immunodeficiency disorder |
Subject to frequent and recurrent infection |
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Primary immunodeficiency |
Inborn, Caused by genetic or developmental defect in the immune system, SCID (severe combined immunodeficiency)- few or no immune cells produced |
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Secondary immunodeficiency |
Acquired, Develops following exposure to a chemical or biological statement |
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AIDS |
Acquired Immune Deficiency Syndrome, caused by HIV 1 and HIV 2 |
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HIV |
Human immunodeficiency virus, retrovirus, targets helper T cells. |
| Add or remove terms from this set |
