Growth of Bacteria on Agar Plates
Bacteria Prac
Aim: To observe the growth of bacteria on Agar plates
Hypothesis: That the bacteria will grow in colonies throughout the agar plates except for the one with the anti-biotic loop because some will fight off the bacteria. Method: (Method taken from prac sheet) Plate 1: Use the swab to cover your entire agar plate in your bacteria. You only need one swab of bacteria but be careful to cover the entire surface of your agar in a layer of bacteria. Carefully place an Antibiotic Mastring on top of the agar (use tweezers) in the centre of the plate, being careful not to touch the agar or ring. Place lid back on. Plate 2: Divide your plate in half (imaginary) and each group member press one finger print onto one side of the agar (take care not to press too hard and break through the agar). After each member has their fingerprint on one side of the plate go and wash your hands properly (use soap) and come back and press that same finger each onto the other side of the agar plate gently. Place lid back on and pop upside down. Plate 3: Set up a Bunsen burner on a heat proof mat and get an inoculating loop. Carefully swab some of your bacteria into one corner of your agar plate. Disinfect your loop in the Bunsen flame and then place carefully on the ‘corner’ where you swabbed the bacteria. Carefully drag the bacteria across onto the next ‘corner’ of your agar plate in the clockwise direction. Disinfect the loop again in the Bunsen. Repeat by placing the loop carefully on the last lots of bacteria moved and move again onto the next ‘corner’ of the plate. Disinfect loop again and place carefully onto most recently moved bacteria and drag across carefully to the last ‘corner’ of your plate. Disinfect loop before finishing up, place lid on plate and tip upside down. Make sure your lids are on tight and your group’s three plates labelled clearly and place together on bench. They will be moved to a warm spot between now and next lesson.
Results: (Represented on a
Aim: To observe the growth of bacteria on Agar plates
Hypothesis: That the bacteria will grow in colonies throughout the agar plates except for the one with the anti-biotic loop because some will fight off the bacteria. Method: (Method taken from prac sheet) Plate 1: Use the swab to cover your entire agar plate in your bacteria. You only need one swab of bacteria but be careful to cover the entire surface of your agar in a layer of bacteria. Carefully place an Antibiotic Mastring on top of the agar (use tweezers) in the centre of the plate, being careful not to touch the agar or ring. Place lid back on. Plate 2: Divide your plate in half (imaginary) and each group member press one finger print onto one side of the agar (take care not to press too hard and break through the agar). After each member has their fingerprint on one side of the plate go and wash your hands properly (use soap) and come back and press that same finger each onto the other side of the agar plate gently. Place lid back on and pop upside down. Plate 3: Set up a Bunsen burner on a heat proof mat and get an inoculating loop. Carefully swab some of your bacteria into one corner of your agar plate. Disinfect your loop in the Bunsen flame and then place carefully on the ‘corner’ where you swabbed the bacteria. Carefully drag the bacteria across onto the next ‘corner’ of your agar plate in the clockwise direction. Disinfect the loop again in the Bunsen. Repeat by placing the loop carefully on the last lots of bacteria moved and move again onto the next ‘corner’ of the plate. Disinfect loop again and place carefully onto most recently moved bacteria and drag across carefully to the last ‘corner’ of your plate. Disinfect loop before finishing up, place lid on plate and tip upside down. Make sure your lids are on tight and your group’s three plates labelled clearly and place together on bench. They will be moved to a warm spot between now and next lesson.
Results: (Represented on a