rpa - cultivating bacterial culture

• Why do scientists incubate bacteria at 37 degrees but students incubate at 25 degrees?

  • Human body temperature = 37 degrees.
  • Salmonella would grow better at 37 degrees.
  • 25 degrees reduces the growth of bacteria that would be harmful for the students.
• Why do cells burst?

  • Water enters the cell by osmosis.
  • Without a cell wall bacteria cannot withstand the water and will burst.
• What are the examples of aseptic techniques?

  • Sterilise/disinfect hands/work surface.
  • Sterilise petri dish before use.
  • Pass forceps through flame before use.
  • Work near a flame.
  • Secure lid of petri dish with tape.