unit 15 Task 1
Iman boukjija zamani
11053457
Part A
Write up of experiments
Preparation of the agar plate
An agar plate is a Petri dish that contains a solid growth medium, typically agar plus
nutrients, used to culture small organisms such as microorganisms. Sometimes selective
compounds are added to influence growth, such as antibiotics.
Equipment:
- Liquid agar at 50°C
- Sterile petri dish
- Bunsen burner
- Matches
- Marker pen
Procedure:
1. Work near a lighted bunsen hot air rises so the heated air around a lit bunsen burner
creates a slight current upwards. This means that any “hovering” contaminants in the
air are wafted away from your work area, instead of falling into your work
2. Open the McCartney bottle of agar and pass the rim trough the bunsen flame to kill
any bacteria, that might be in the rim of the bottle or near it.
3. Open petri dish away from you and pour all the agar into the dish.
4. Close the dish immediately and swirl to ensure that agar covers all the base of the
dish.
5. Leave undisturbed to set.
6. Once the agar has set store the plate upside down until needed (Plates are
incubated upside down (agar up), so that condensation does not drip onto the plate
and interfere with the developing microbes).
Risk assessment Agar plate
50 °C water bath is needed to store the molten agar
To prevent the agar from contaminating, the water bath must be at the right depth, the
bottles of molten agar are stored well in the water bath, the outside of the bottle is wiped
before used, also using antiseptic techniques, like flaming the neck of the bottle, to kill any
bacteria, as well as opening the petri dish just a little bit, so we can pour the agar, without
any contamination.
When pouring the agar, in the petri dish we must make sure that it is well ayed, with no
bulbs or visible contamination.
Inoculating loop, The loop is inoculated, from the base to prevent any contamination, it is
left to cool, before proceeding.
Hair must be kept tied back, and bunsen burner on a orange flame to prevent burning
ourselves, with the blue invisible flame.
Bacteria is very present in all the experiments, so gloves must be worn, never put hand in
our mouth.
Wipe surface area well with sterilizing spray and dry with tissue.
Preparation of the inoculated McCartney bottle