DEFINITION OF 
   MICROBIOLOGY
   • …the study of those organisms best 
     observed with the aid of a microscope.
   • …employs techniques and procedures 
     required to study microorganisms.
        FIELDS OF MICROBIOLOGY
        •  Bacteriology – prokaryotic cells
        •  Virology – viruses
        •  Mycology – fungi
        •  Protozoology – protozoans (single celled 
           prokaryotes)
        •  Parasitology – parasites
        •  Immunology
        •  Medical Microbiology
        •  Microbial Genetics
        •  Microbial Ecology
        •  Biotechnology
   ANTHON VAN LEEUWENHOEK
            • (1632 – 1723)
            • Dry goods merchant
            • Lens grinder
            • Produced simple (single 
             lens) microscopes
            • In report dated Oct 9 
             1676 is the first 
             description of bacteria.
   LOUIS PASTEUR
                • (1822 – 1895)
                • Frenchman trained as a 
                 chemist.
                • Discovered isomers of 
                 tartaric acid.
                • Discovered the process of 
                 fermentation and 
                 developed a method of 
                 “pasteurization” to reduce 
                 microbial contamination of 
                 wine and beer.
                • Developed anthrax and 
                 rabies vaccines.
   WHAT CAUSED DISEASE?
   • Humoral theory – an imbalance of the four 
    body humors (black bile, yellow bile, phlegm, 
    blood) resulted in disease. Treatments: 
    bloodletting, expectorants, purgatives.
   • Demonic theory – cast out the demons; 
    exorcists conducted this practice.
   • Miasmatic theory – “something in the air” 
    (miasma = poisonous vapor); malaria = bad 
    air; influenza = influence of the stars.
   • Germ theory – particulate matter transmissible 
    from one person to another initiated disease.