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30 Cards in this Set

  • Front
  • Back
Invasion of the body by a microorganism
An organism that causes disease.
A poisonous substance produced by a microorganism.
An insect, rodent, or other organism that carries and transmits a pathogen from one host to another.
A system of vessels and organs that picks up excess fluid, proteins, lipids, and other substances from the tissues; filters out pathogens and other waste products; and returns the cleansed fluid to the general circulation.
lymphatic system
An infection spread by the blood or lymphatic system to large portions of the body.
A type of white blood cell that engulfs foreign organisms and infected, damaged, or aged cells; particularly prevalent during the inflammatory response.
A large phagocytic (cell-eating) cell that devours foreign particles.
A type of white blood cell that directly destroys virus-infected cells and cancer cells.
natural killer cell
A white blood cell specialized to activate T and B cells.
dendritic cell
A white blood cell continuously made in lymphoid tissue as well as in bone marrow
lymphocyte .
A lymphocyte that arises in bone marrow and matures in the thymus (thus its name).
T cell
A lymphocyte that matures in the bone marrow and produces antibodies.
B cell
A lymphocyte that helps activate other T cells and may help B cells produce antibodies
helper T cell
A lymphocyte that kills body cells that have been invaded by foreign organisms; also can kill cells that have turned cancerous.
killer T cell
a lymphocyte that inhibits the growth of other lymphocytes
suppressor T cell A lymphocyte that inhibits the growth of other lymphocytes.
a specialized protein, produced by white blood cells, that can recognize and neutralize specific microbes
antibody A specialized protein, produced by white blood cells, that can recognize and neutralize specific microbes.
Lymphocytes generated during an initial infection that circulate in the body for years, "remembering" the specific antigens that caused the infection and quickly destroying them if they appear again.
memory T and B cells
A disease in which the immune system attacks the person's own body.
autoimmune disease
A marker on the surface of a foreign substance that immune system cells recognize as nonself and that triggers the immune response.
A chemical responsible for the dilation and increased permeability of blood vessels in allergic reactions.
A chemical messenger produced by a variety of cell types that helps regulate many cell functions; immune system cells release cytokines that help amplify and coordinate the immune response.
Mechanisms that defend the body against infection; specific defenses against specific pathogens
The body's ability to mobilize the cellular "memory" of an attack by a pathogen to throw off subsequent attacks; acquired through vaccination as well as the normal immune response.
acquired immunity
The period when bacteria or viruses are actively multiplying inside the body's cells; usually a period without symptoms of illness.
The stage of an infection, after incubation, during which initial symptoms begin to appear but the host does not feel ill; a highly contagious period
prodromal period
A preparation of killed or weakened microorganisms, inactivated toxins, or components of microorganisms that is administered to stimulate an immune response; a vaccine protects against future infection by the pathogen.
A disorder caused by the body's exaggerated response to foreign chemicals and proteins; also called hypersensitivity.
A substance that triggers an allergic reaction
allergen .
A severe systemic hypersensitive reaction to an allergen characterized by difficulty breathing, low blood pressure, heart arrhythmia, seizure, and sometimes death.