6. Three Nutrient Agar Plate (NAP) were contaminated as follow to illustrate that there are microorganism all around us and to demonstrate the necessity for proper aseptic technique.
a) The lid of the first agar plate was removed and the exposed agar was placed in the building on the laboratory rack for 3 hours. The lid was replaced and labelled as “air”. It was then incubated at room temperature.
b) A second Petri plate was divided in half using a marker. Two cotton sterile swab were moisten in sterile water. One of the swab was rubbed over one of the stool in the laboratory and the other swab was rubbed over the sink in the laboratory. Both swabs were used to inoculate the each of the halves of the second Petri plate respectively. The plate …show more content…
The size of the single colony observed is small for both Petri plate 1 and Petri plate 3. Most of the morphology of bacteria in Petri plate 1 and Petri plate 2 are the same except for the appearance and optical property. The appearance of bacteria in Petri plate 1 was dull while for the Petri plate 2 the appearance was glistening. Another difference is bacteria in Petri plate one has translucent optical property while bacteria in Petri plate 2 was opaque.
The small amount of airborne contaminants in Petri plate one was maybe because of the air in the laboratory was clean.
There might be an error while contaminating the second Petri plate as no bacteria colony was observed on the surface of agar plate. The stool and sink in the laboratory was probably disinfected with 70% alcohol and anti-bacterial agent before the experiment was done resulting in the lack of microorganism growth on the agar surface. The bacteria might also be obligate anaerobes that cannot live in the presence of
a) The lid of the first agar plate was removed and the exposed agar was placed in the building on the laboratory rack for 3 hours. The lid was replaced and labelled as “air”. It was then incubated at room temperature.
b) A second Petri plate was divided in half using a marker. Two cotton sterile swab were moisten in sterile water. One of the swab was rubbed over one of the stool in the laboratory and the other swab was rubbed over the sink in the laboratory. Both swabs were used to inoculate the each of the halves of the second Petri plate respectively. The plate …show more content…
The size of the single colony observed is small for both Petri plate 1 and Petri plate 3. Most of the morphology of bacteria in Petri plate 1 and Petri plate 2 are the same except for the appearance and optical property. The appearance of bacteria in Petri plate 1 was dull while for the Petri plate 2 the appearance was glistening. Another difference is bacteria in Petri plate one has translucent optical property while bacteria in Petri plate 2 was opaque.
The small amount of airborne contaminants in Petri plate one was maybe because of the air in the laboratory was clean.
There might be an error while contaminating the second Petri plate as no bacteria colony was observed on the surface of agar plate. The stool and sink in the laboratory was probably disinfected with 70% alcohol and anti-bacterial agent before the experiment was done resulting in the lack of microorganism growth on the agar surface. The bacteria might also be obligate anaerobes that cannot live in the presence of