Culturing microorganisms

• You need to use uncontaminated cultures as they can affect your results therefore you can avoid this by:

  • sterilise the inoculating loop by passing it through a flame
  • the lid of the petri dish should be lightly taped on to stop microorganisms getting in
  • the Petri dish should be stored upside down to stop drops of condensation falling onto the agar surface
• • You can grow bacteria in a lab and in industrial conditions cultures are incubated at higher temperatures so they can grow a lot faster
  • however in schools it cant exceed temperatures of 25 degrees as harmful pathogens are more likely to grow
• to calculate area of an inhibition zone you use this formula:

  $\pi r^2$