MGY377H1 Lecture Notes - Cowpox, Geochemistry, Nitrogen Cycle
Document Summary
Microbiology is the study of microorganisms (or microbes) Microbes are microscopic: through most of their lifespan, can only be seen through a microscope, less than about 1 mm across, about 10-7 m to 10-3 m in size. Six major groups of microbes: prokaryotes. In 1990, infectious diseases were the biggest killer. In 2004, lower respiratory infections are in the top 10 but mostly in elderly due to improvements in public health. Discovery of microbes: hooke observes small eukaryotes (1600, leeuwenhoek discovers bacteria (1676) Developed lenses to look at fibers of the cloth. Developed powerful lenses to look at bacteria. Microbes are living organisms: microbes arise only from other microbes. No spontaneous generation: redi shows that flies do not spontaneously generate (1688, pasteur shows that microbes do not grow in liquid until introduced from outside (1861) Long curved neck doesn"t allow bacteria to fall inside. Broken neck allows bacteria to fall inside and grow in medium.