Transcript Document
Immunity from Disease What is a infectious disease? • Pathogen causes A change that disrupts the homeostasis in the body. Main agents can be – Bacteria – Protozoans – Fungi – Viruses Sources can be soil contaminated water and infected animals (that includes us) Bacteria QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. Two Protozoans (and a Sponge) for 4 Flutes • The protozoans, of which there are over 30,000 species, are primitive, single-celled organisms, of which the best known example is probably the amoeba. Paramecium caudatum is one of the most common freshwater ciliates. The nastysounding Plasmodium virax is the malaria parasite; like many parasites it has a complex life-cycle involving several hosts, and exists in several forms. Sponges are the most primitive group of multi-cellular animals. The Bath Sponge Euspongia mollissima finds itself in this piece on the strength of it's mellow name. QuickTime™ and a TIFF (Uncompressed) decompressor are needed to see this picture. Fungi • • • • • • The Kingdom Fungi are important organisms, both in terms of their ecological and economic roles. They breaking down dead organic material, , most vascular plants could not grow without the symbiotic fungi, or mycorrhizae, that inhabit their roots and supply essential nutrients . Other fungi provide numerous drugs (such as penicillin and other antibiotics), foods like mushrooms, truffles and morels, and the bubbles in bread, champagne, and beer.Fungi also cause a number of plant and animal diseases: in humans, ringworm, athlete's foot, and several more serious diseases are caused by fungi. . Plant diseases caused by fungi include rusts, smuts, and leaf, root, and stem rots, and may cause severe damage to crops. http://www.ucl.ac.uk/Pharmacology/dc-bits/fungi-pics1-04m.jpg •http://www.microbe.org/microbes/fungi1.asp •http://waynesword.palomar.edu/ww0504.htm •http://waynesword.palomar.edu/slime1.htm Viruses • Made of protein coat • Are they living? – What are the criteria for life? • • • • Don’t respire Don’t grow Don’t develop CAN make copies of themselves but only with hosts help • Named after the illness or organ they infect. From birth symbiotic relationships are established • You are “inoculated” with microorganisms on your • skin • upper respiratory system, • lower urinary and reproductive tracks • Lower intestinal track How they help • They maintain equilibrium within the body by keeping other microorganisms from growing • Can become potential pathogens when – Conditions change and helpful organisms are eliminated – Beneficial bacteria enter areas of the body where they are not normally found – Body becomes weakened or injured Infectious disease • Caused by the presence of pathogens • • • • • Not all diseases caused by pathogens some are Inherited Caused by wear and tear Caused by exposure to chemicals (cirrhosis ) Malnutrition (scurvy) What do we use to figure out if it’s a pathogen? • • • • • Koch’s postulates 1 2 3 4 How are Pathogens Spread • Must have continual source of the pathogen – Living • Carriers human/ other animals – Incubation period- don’t show it yet – Dead – Inanimate object soil/ water • Fungi • botulism • Intestinal parasites from water Transmission • Four ways – – – – Direct contact- Cold, STD’S By an object- money, toys, towels Through the air- Cough, sneezes.. By an intermediate organism (vector) • West Nile virsus• Lyme disease• Bubonic plague How do pathogens damage you Patterms of diease Treatment