10 Pathogens

• 4 major types of pathogens


  bacteria, virus, fungi, protoza
• direct ways of pathogens being transmitted 


  touch each other, can pass from mother to baby through the placenta, through the air
• indirect ways to transmit pathogens


  touching the same object, can be carried by an animal or an insect
• cilia


  small hairs that exist in the noose and throat which work with the mucus to prevent microbes entering through airways
• skin 


  forms a protective barrier around the body
• stomach acid


  the low pH kills many pathogens
• mucus


  slimy substance that works with the cilia to catch pathogens entering the mouth and nose and flush them out
• how to reduce spread of disease

  clean water supply, hygienic food preparation, waste disposal, sewage treatment
• what are antigens


  a substance that triggers the specific immune response is called antigen
• antigens include glycoproteins
• self antigens occur on the surface of the plasma membrane on every cell of an individual's body
• non-self antigens occur on the cell wall or surface membrane of all other organisms, including pathogens and cells from other humans (except in identical twins)
• if a pathogens enters the bloodstream, it encounters numerous B-lymphocytes. a few will have the correct receptor to attach to the antigen on the pathogen. once attached, the B-lymphocytes divide rapidly, producing large numbers of genetically identical daughter cells
• some of the daughter cells develop into plasma cells, plasma cells secrete anti-body
• finally some daughter cells develop into memory cells, which remain in the circulation without producing antibody. these are ready to respond if the antigen returns
• plasma cells can secrete up to 2000 molecules of specific antibody per second
• antibody is a globular protein because it is involved in the immune response it is called an immunoglobulin
• antibodies help to eliminate pathogens in a number of ways, one of these is called agglutination
• this happens when the two binding sites on the antibody molecule attach to antigens on two separate pathogens. this produces a lattice like complex
• agglutination causes the pathogen to clump together making them easier to be engulfed by phagocytes or destroyed by complement proteins