MCB 11 - 1ST MODULE

Cards (60)

  • Microbiology is the Study of organisms and agents too small to be seen by the naked eye (<1mm)
  • Microbiology is the study of organisms that can exist as single cells (others are acellular), contain a nucleic acid genome for at least some part of their life cycle, and are capable of replicating that genome
  • Epulopiscium lives in the gut of sturgeonfish.
  • T. magnifica (2022) has an average cell length of 9000 µm and larger than Thiomargarita namibiensis.
  • The science of microbiology revolves around two interconnected themes:

    1. Understanding the living world of microscopic organisms (as a basic biological science)

    2. Applying our understanding of microbial life processes for the benefit of humankind and planet Earth (as an applied biological science)
  • Importance of microorganisms:
    first living organisms on planet
    live everywhere life is possible
    more numerous than any other kind of organisms
    global ecosystem depends on their activities
    influence human society in many ways
  • Basic Microbiology: Interest in specific group of microorganisms and their biology.
  • Virology studies viruses. Mycology studies fungi. Phycology: algae Protozoology: protozoa Bacteriology: bacteria
  • Applied Microbiology: Applying our understanding of microbial life processes for the benefit of humankind and planet Earth.
  • fields of microbiology
    • Medical Microbiology
    • Immunology
    • Public Health Microbiology
    • Food & Dairy Microbiology
    • Industrial Microbiology
    • Agricultural Microbiology
    • Microbial Ecology
  • Yeast is a microorganism. Its cells metabolize the carbohydrates in flour and produce carbon dioxide, which causes the bread to rise.
  • Saccharomyces cerevisiae, the yeast responsible for making bread rise
  • Ötzi the Iceman was Infected with the eggs of the parasite Trichuris trichiura, which may have caused him to have abdominal pain and anemia
  • Otzi infected with Borrelia burgdorferi, a bacterium that causes Lyme disease
  • Ötzi may have been trying to treat his infections with the woody fruit of the Piptoporus betulinus fungus. This fungus has both laxative and antibiotic properties.
  • Ancient Greeks attributed disease to bad air, mal’aria, which they called “miasmatic odors.”
  • The Romans also believed in the “miasma” hypothesis and created a complex sanitation infrastructure to deal with sewage.
  • In Rome, they built aqueducts, which brought fresh water into the city, and a giant sewer, the Cloaca Maxima, which carried waste away and into the river Tiber.
  • Zacharias Janssen
    • invented the first compound microscope (3-10x)
  • Athanasius Kircher
    • suggested to be the first to observe microorganisms (20 years before Hooke’s observation; 29 years before van Leeuwenhoek)

    wrote a book chapter, in Latin: “Concerning the wonderful structure of things in nature, investigated by Microscope”
  • Antonie van Leeuwenhoek (1676)
    -“wee animalcules”
  • Robert Hooke
    • simple compound microscope (30x)
    • “cells” in cork 

    “elongated stalks” (fungi)
  • Spontaneous Generation Theory
    -Life emerges from non-living matter;
    -“vital force” required
  • Biogenesis Theory
    -“Life begets life”
  • Hippocrates, the “father of Western medicine,” believed that diseases had natural, not supernatural, causes
  • The historian Thucydides observed that survivors of the Athenian plague were subsequently immune to the infection.
    "the father of scientific history"
  • Marcus Terentius Varro proposed that disease could be caused by “certain minute creatures . . . which cannot be seen by the eye.”
  • Francesco Redi
    -jar & meat experiment (no eggs on meat when jar was sealed)
  • John Needham
    chicken broth, put it into a flask, sealed it, and waited. Soon enough, microorganisms grew. Because of this, people started to believe in Spontaneous Generation even more.
  • John Needham's broth became cloudy due to growth of microorganisms.
  • Lazzaro Spallanzani
    -disproved John Needham's experiment by using broth in a flask, sealed the flask so that way no air could get in, and boiled it. No organisms grew in that flask. 
  • Spontaneous Generation supporters claimed that air was required
    for the vital force to work.
  • Franz Schultze – passed air through strong acids
  • Theodor Schwann – passed air through red-hot tubes
  • Georg Friedrich Schröder & Theodor von Dusch (1850) - filtered air through sterile cotton wool
  • Louis Pasteur
    • Experiments with Swan-neck flasks
    Results proved that life did not arise from non-life
  • John Tyndall
    ➢ demonstrated that dust carries microorganisms
    ➢ also provided evidence for the existence of exceptionally heat resistant forms of bacteria
    ➢ Developed the process of “tyndallization”
    -delivered the final blow to the spontaneous generation theory
  • GERM THEORY OF DISEASE
    -Diseases are caused by specific agents called germs
  • Girolamo Fracastoro
    • disease was caused by invisible living creatures
  • Agostino Bassi
    • showed that a disease of silkworms was caused by a fungus