History of Microbiology Flashcards
What is microbiology?
Study of organisms too small to be seen with the naked eye - bacteria, fungi, viruses, helminths (worms), & protozoa
What did Robert Hooke discover?
1665 - living things composed of little boxes (cells)
What did Antoni von Leeuwenhoek do?
First to visualise bacteria - x266 magnification - microorganisms he observed in teeth scrapings, rainwater, & peppercorn infusions
Explain the development of the microscope?
17th Century - single lens
19-20th Century - modern light microscope
1931 - electron microscope
1957 - confocal microscope
1968 - atomic force microscope
2017 - cryo-electeon microscopy
What did Dubochet, Frank, & Henderson discover?
Cryo-electron microscopy in 2017 - freeze biomolecules mid-movement - visualise processes - understanding & development of pharmaceuticals
What theory did Von Helmont propose?
Spontaneous generation (false) - organisms arise from non-living materials - vital force - putrefaction (we now know m/o introduced via air) & experiment wheat & sweaty clothes in jar after 21 days mice found in jar
What is biogenesis?
Living organisms arise from pre-existing life
What scientists are known as the golden age of microbiology?
Louis Pasteur, Ferdinand Cohn, Joseph Lester, Robert Koch
What work did Francesco Redi do?
1668 - Disproved spontaneous generation - maggots did not appear on sealed jars as flies couldn’t reach meat, unopened meat rotted due to flies laying eggs & maggots eating meat, maggots appear on mesh covering as flies lay eggs on mesh
Talk about Ferdinand Cohn’s work?
Founded bacteriology - heat resistant spores in bacillus
Talk about John Tyndall’s work?
Disproved spontaneous generation - Tyndillisation (Heat to 100° for 15 minutes on 3 successive days - heat resistant spores germinate after heat exposure and are killed)
Talk about Joseph Lister’s work?
Discovered surgical infections were caused by microbes - antiseptic technique - carbolic acid (phenol) at disinfects site, surgeons wear gloves - increased survival rate & decreased mortality rate at childbirth
Talk about Louis Pasteur’s work?
Disproved spontaneous generation - non-sterile liquid poured into flask - neck of flask drawn out in flame - liquid sterilised - dust &m/o get trapped in bend of the neck of the flask - if upright flask remains sterile, if tipped microbes mix with sterile liquid & putrefaction occurs - microbes cause fermentation (conversion of sugar to alcohol - beer & wine - porcelain filter) - microbes cause food spoilage - Pasteurisation (liquid treated with mild heat to extend shelf life) - support germ theory of disease - vaccine for anthrax, fowl cholera, rabies
Explain Robert Koch’s work?
Germ theory of disease, solid plates & pure culture, Bacillus anthracis causes anthrax, Vibrio causes cholera, Mycobacterium tuberculosis uses to prove Koch’s postulates
Explain Koch’s postulates?
1) Suspected pathogen must be present in all cases of disease & absent from healthy animals
2) Suspected pathogen must be grown in pure culture
3) Cells from a pure culture of the suspected pathogen must cause disease in a healthy animal
4) Suspected pathogen must be reisolated & shown to be the same as the original
