4.1.1.6 culturing microorganisms

• how often can bacteria multiply by binary fission?

  Every 20 minutes if they have enough nutrients and suitable temperature
• where can bacteria be grown?

  in a nutrient broth solution or as colonies on an agar gel plate
• what are uncontaminated cultures of microorganisms required for?

  investigating the action of disinfectants and antibiotics
• why must Petri dishes be sterilised before use?

  contamination that can cause mutations
• why should cultures be incubated at a maximum temperature of 25°C in schools or college labs?

  There would be a high risk of creating a dangerous pathogen
• what are other ways to stop contamination when culturing bacteria?

  
  

  • Sterilise the inoculating loops by passing them through a flame
  • The lid of the Petri dish should be secured with adhesive tape and stored upside down