Ch. 24 Immune System Flashcards
Neutrophils
a nonspecific defensive, phagocytic white blood cell that can engulf bacteria and viruses in infected tissue; has a multi-lobed nucleus
Monocytes
a phagocytic white blood cell that can engulf bacteria and viruses in infected tissue; has a large oval or horseshoe-shaped nucleus
Macrophages
a large, amoeboid, phagocytic white blood cell that develops from a monocyte
- “Big Eater”
- Wander actively in interstitial fluid to eat bacteria and virus infected cells
Natural Killer Cells
a nonspecific defensive cell that attacks cancer cells and infected body cells, especially those harboring viruses
Interferon
a nonspecific defensive protein produced by virus-infected cells and capable of helping other cells resist viruses
- Short term and most effective against influenza/cold
- Made by body in small quantity, use recombinant DNA
Complement Proteins
a family of nonspecific defensive blood proteins that cooperate with other components of the vertebrate defense system to protect against microbes; can enhance phagocytosis, directly lyse pathogens, and amplify the inflammatory response
Inflammatory Response “setting on fire”
a nonspecific body defense caused by a release of histamine and other chemical alarm signals, which trigger increased blood flow, a local increase in white blood cells, and fluid leakage from the blood. The results include redness, heat, and swelling in the affected tissues.
- Aims to disinfect and clean injured tissues
- Helps to prevent the spread of infection to surrounding tissues
Histamine
a chemical signal released by injured cells that causes blood vessels to dilate during an inflammatory response
Lymphatic System
the organ system through which lymph circulates; includes lymph vessels, lymph nodes, and the spleen. The lymphatic system helps remove toxins and pathogens from the blood and interstitial fluid, and returns fluid and solutes from the interstitial fluid to the circulatory system
Lymph
a fluid similar to interstitial fluid that circulates in the lymphatic system
What are the functions of the lymphatic system?
1) return tissue fluid to circulatory system
2) fight infection
Immune System
the organ system that protects the body by recognizing and attacking specific kinds of pathogens and cancer cells
- More effective than nonspecific resistance → amplifies certain nonspecific responses
- Extremely specific and has remarkable “memory” for antigens it has encountered before → react faster
Antigen
a foreign (nonself) molecule that elicits an immune response
Antibody
a protein dissolved in blood plasma that attaches to a specific kind of antigen and helps counter its effects
Immunity
resistance to specific body invaders
- Acquired by natural infection or vaccination
Vaccination
a procedure that presents the immune system with a harmless variant or derivative of a pathogen, thereby stimulating the immune system to mount a long term defense against the pathogen
Vaccine
a harmless variant or derivative of a pathogen used to stimulate a host organism’s immune system to mount a long term defense against the pathogen
Active Immunity
body is stimulated to produce antibodies in its own defense
Passive Immunity
temporary immunity obtained by acquiring ready-made antibodies or immune cells; lasts only a few weeks or months because the immune system has not been stimulated by antigens
Lymphocytes
a type of white blood cell that is chiefly responsible for the immune response; found mostly in the lymphatic system
B Cells
a type of lymphocyte that matures in the bone marrow and later produces antibodies; responsible for humoral immunity
T cells
a type of lymphocyte that matures in the thymus and is responsible for cell-mediated immunity; also involved in humoral immunity
Humoral Immunity
the type of specific immunity brought about by anti-body producing B cells; fights bacteria and viruses in body fluids
- Antibodies carries in lymph/blood to site of infection
- Can be passively transferred by injecting blood plasma