Biology 2.7

• Freezing stops bacteria growth and refrigerating slows bacteria growth down
• Bacteria grows rapidly at around room temp and above more slowly at higher temperatures
• Most bacteria are killed by boiling
• 4 methods on how to inoculate plates

  1 loop is sterilised by placing it in flame ( heat will kill any microorganism)

  2 place the inoculating loop into the sample

  3 sweep the loop across the surface of the agar being carefull not to dig in

  4 seal it with sellotape in a cross to allow oxeygon to diffuse in, plates are innovated at 25•c to encourage growth
• What is agar

  A nutrient helly used to grow cultures
• what is a inoculating loop 


  A sterile loop used to transfer bacteria onto an agar plate
• What is a Petri dish used with cros tape

  To prevent entry and exit of bacteria
• What is aseptic 


  A sterile working technique that avoids contaminatinon
• What is planting 


  growning a culture of bacteria on a sterile Petri dish
• Each bacterial colony is formed from one bacterium
• Sometimes its difficult to count colonies of they have grown to close toghert ‘Clumping’
• What is a fermenter 


  a machine which is used commercially to green microorganisms such as penicillin
• Ferment machine 


  Photo

  
• Give the name and type of microorganisms that produce’s penicillin

  Penicillium finger
• 5 things that must be kept at a certain condition in a fermenter

  Temp (maintained by colling water jacket)

  pH

  air

  nutrients
• Fungus penicillium grows within the fermenter and releases the antibiotic into the surroundings medium, the medium is then filtered upon competition and penecilin is extracted
• What is bacteria and fungie grown on

  A Petri dish
• Why must the Petri dish be sterilised before

  To prevent contamination by killing. Unwanted microbes
• Why is the solution in a fermenter constantly stirred

  So the fungus doesn’t clump