Information on microbes and microbe research




  • Spontaneous generation did not occur
  • 2 flasks both boiled to sterilise them: one open and one sealed
  • Microbes grew in the open one but not the sealed one


  • Sterilised air through red-hot tubes or bubbling it throguh sulfuric acid
  • Oxygen levels stayed the same but when bubbled through boiled broth, nothing grew
  • If normal air was used, microbes grew - proving there were microbes in the air


  • Used swan necked flasks in a similar experiment
  • Broke the neck of one off
  • Microbes grew in the flask without the swan neck
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Types of microbe

  • Fungi
  • Bacteria
  • Viruses
  • Single-celled organisms
  • Aseptic techniqe reduces the amount of contamination
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  • Yeast - a single celled organism used in baking and brewing
  • Fermentation- asexual reproduction - budding!
  • Ethanol and Carbon dioxide produced with anaerobic respiration
  • Used in the making of beer and wine: brewing
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Beer and Wine making


  • Starch in barley grains broken down into a sugary solution by enzymes in the germinating grains: process called MALTING
  • Sugary solution then FERMENTED
  • Hops are added to give extra flavour


  • Same process as above BUT the sugars in the grapes provide an energy source for the yeast
  • Different grapes and time of fermentation give different flavours to the wine
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Yoghurt production

  • A starter culture of bacteria is added to warm milk
  • Bacteria ferment the lactose in the milk - this produces lactic acid
  • The acid clots and solidifies the milk, turning it into yoghurt
  • Other benefits of the production of lactic acid: -It prevents the growth of other bacteria -It gives the yoghurt a tangy flavour
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An industrial fermenter


  • Keeps the microbes in suspension
  • Keeps the temperature even (No hot spots)

Water jacket

  • Removes excess heat prodcued during respiration
  • Stops the enzymes and microbes from denaturing


  • Monitor the Ph and temperature

Air supply

  • Provides oxygen for respiration
  • Stream of bubbles helps to mix the solution
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Other uses of microbes


  • Food source - Fusarium - Mycoprotein
  • Antibiotics e.g penicillin from penicillium: produced where nutrients are scarce because it produced penicillin to detroy other bacteria
  • Fuels BIOGAS from the fermentation of sewage BIOFUELS from sugar cane and ethanol
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