Video

• What type of bacterial culture is being used in the practical?

  A safe strain of E. coli
• Why must you handle the bacterial culture as if it were dangerous?

  To maintain safety and sterility
• What should you do before starting the practical?

  Wash your hands thoroughly
• Where should you open the lid of the agar plate?

  Near the Bunsen burner
• What is the purpose of the Bunsen burner in the practical?

  To create a sterile area
• How should you label the agar plate?

  At the bottom, not the lid
• Why is it important to write the date on the agar plate?

  To track how old the culture is
• What should you do if you accidentally touch a non-sterile surface?

  Wash your hands again
• What flame should the Bunsen burner be turned to for sterilization?

  Blue flame
• How is the sterile pipette sterilized?

  Wrapped in red paper and heated
• What is the correct method to handle the pipette?

  Hold it by the blunt end
• Why do you flame the lid of the bacteria bottle?

  To sterilize it before use
• How should you inoculate the agar plate?

  Open the lid briefly and squirt
• What happens if you break the surface of the agar?

  Bacteria won't grow correctly
• What is used to kill any remaining bacteria on the spreader?

  Vinegar
• What is a lawn of bacteria?

  A dense growth of bacteria on agar
• What is the purpose of the antibiotic disk in the experiment?

  To test its effectiveness against bacteria
• What is the expected outcome of using the antibiotic disk?

  Clear ring around the disk indicates effectiveness
• How should the agar plate be stored after inoculation?

  Upside down to prevent condensation
• Why is it important to seal the agar plate with tape?

  To prevent contamination while allowing oxygen in
• What temperature should the agar plates be incubated at?

  30 degrees Celsius
• What should you do if the agar plate is completely covered after incubation?

  It indicates overgrowth of bacteria
• What does a cloudy agar plate indicate?

  Bacteria are growing and dividing
• How can you measure the effectiveness of the treatments?

  By measuring the diameter of clear areas
• What factors should be considered for a fair test?

  Viscosity of liquids and diffusion rates
• How can results from this experiment be applied to real-world situations?

  To determine effective treatments for bacterial infections
• What is the best treatment based on the experiment?

  Tea tree oil showed the best effectiveness
• Why might tea tree oil not be suitable for treating bacterial infections?

  It may not be safe for ingestion
• What are the steps to prepare and inoculate an agar plate?

  1. Wash hands thoroughly.
  2. Set up equipment in a sterile area.
  3. Label the agar plate at the bottom.
  4. Inoculate the plate with bacteria using a sterile pipette.
  5. Spread the bacteria evenly with a sterile spreader.
  6. Incubate the plate at 30 degrees Celsius.
• What are the considerations for analyzing the effectiveness of antibacterial treatments?

  • Measure the diameter of clear zones.
  • Ensure a fair test by controlling variables.
  • Compare results across multiple trials.
• What are the potential outcomes of the experiment with the antibiotic and antiseptics?

  • Clear zones indicate effectiveness.
  • Compare the size of clear zones for effectiveness.
  • Determine the best treatment for bacterial growth prevention.