Required Practicals - Microbiology

Question 1

What are the 5 aseptic techniques used? (Agar Jelly Practical)

Answer 1

-Flaming the neck of the culture bottle

-Lifting the lid of the agar plate at an angle

-Placing drops of culture from the pipette onto the agar

-Spreading the bacteria thoroughly around the agar plate to the edges

-Placing the filter paper discs onto the agar plate in the correct positions

Question 2

What materials do you need for the agar jelly practical?

Answer 2

-a nutrient agar plate inoculated with bacteria
- heatproof mat
- filter paper discs
- three antiseptics
- disinfectant
- forceps
- clear tape
- hand wash
- wax pencil or permanent marker
- access to an incubator set to 25 degrees C

Question 3

What is the aim of the practical? (Agar jelly practical)

Answer 3

To investigate the effect of antiseptics or antibiotics on bacterial growth

Question 4

How do you calculate the zone of inhibition? (Agar Jelly Practical)

Answer 4

Area = pi (3.14) x radius squared

Question 5

What should you always do before the practical? (Agar Jelly)

Answer 5

Ensure the work space and your hands are thoroughly washed

Question 6

What do we do to ensure accurate results? (Agar Jelly Practical)

Answer 6

-Secure the lid using clear tape to prevent aerobic movement of bacteria in.
-Do not fully seal the lid to prevent the bacteria from respiring anaerobically as this can cause dangerous bacteria to grow.