an invasion of body tissues by microorganisms that use the body's environment to multiply and spread disease.
an agent that causes disease
the natural environment for any particular pathogen, where it accumulates in large numbers.
links of the chain
pathogen reservoir portal of exit means of transmission portal of entry new host
Touching contaminated objects Breathing airborne pathogens Bites from infected insects Drinking or eating contaminated water or food
a response to damaged body tissues designed to kill any pathogens in the damaged tissue, promote healing, and prevent the spread of infection to other parts of the body
tiny regions on the surface of an infectious agent that can be detected by B cells and T cells.
proteins released by B cells that bind tightly to infectious agents and mark them for destruction.
3 types of acquired immunity
naturally- having disease artificially- vaccine passively- recieving antibodies
phases of immune response
Phase 1 - Recognition of the invading pathogen (Macrophages, consume the foreign cells., displaying antigen on their surfaces. Helper T cells "read" this information and rush to respond.) Phase 2 - Amplification of defenses Helper T cells multiply rapidly and trigger production of killer T cells and B cells in the spleen and lymph nodes. Cytokines help regulate and coordinate the immune response (interleukins and interferons are two examples). They stimulate increased production of T cells, B cells, and antibodies; promote the activities of natural killer cells; produce fever; and have special antipathogenic properties themselves
Phase 3 - Attack killer Tcells; cell mediated immunity; B cells are sitmulated by Th cells to produce antibody;
Phase 4 - Slowdown--suppressor T cells halt the immune response
chemical responsible for the dilation and increased permeability of blood vessels in allergic reactions; heat, redness, swelling
white blood cell that travels to the blood stream attacking and killing pathogens
natural killer cells
directly destroy virus-infected cells and cells that have turned cancerous.
immune response (stages again)
Phase 1 - Dendritic cells are drawn to the site Phase 2 - Helper T cells multiply Production of Killer T and B cells Phase 3 - Killer T cells strike Cell-mediated immune Anti-body mediated immune response Phase 4 - Last Phase - Suppressor T-cells
ARTIFICIALLY ACQUIRED IMMUNITY (VACCINE)
Introduction of a killed or weakened pathogen to stimulate the body to produce antibodies
the release of histamine and other chemicals into the body leads to a drop in blood pressure, tightening of airways, and possible unconsciousness and even death.
chronic constriction and inflammation of the airways, making breathing difficult and causing shortness of breath, wheezing, coughing, and chest tightness. Allergic asthma (pollen, venom, peanuts, etc.) Intrinsic asthma (exercise or cold)
flu epstein barr hep A, B, C HIV Herpes HPV cannot multiply without body cell
single cell microorg
meningitis (can be life threatening) tuberculosis staph- cause toxic shock MRSA- antiobotic resistant! strep pneumonia- #1 cause of death in kids lyme disease chlamydia, ghonorrhea, syphilis
must get food from organic matter (tissue)
candidiasis histoplasmosis athletes foot, jock itch, ring worm, yeast infection diaper rash trush nail bed infections
multicellular; compete with host body of nutrients tapeworm, pinworm, hookworm
inflammation of the liver that affects liver function. Jaundice Hepatitis A - most widespread form, microscopic amounts of feces from contaminated fruits, vegetables, and ice cubes. Hepatitis B is transmitted through sexual contact. Hepatitis C is the primary reason for liver transplants in the U.S.
other infectious diseases
H1N1 (swine flu) H5N1 (avian influenza or bird flu) SARS (severe acute respiratory syndrome) West Nile virus Hantavirus West Nile virus Severe acute respiratory syndrome (SARS) Rotavirus Escherichia coli Hantavirus - spread by rodents and similar to the flu Ebola