Experiment+6-+Classifications

=Part 1: Catalase=

Before hydrogen peroxide was added

After hydrogen peroxide was added

The conclusion that you can draw from the way the bacteria reacted with the hydrogen peroxide is that the bacteria is not used to those kinds of conditions and therefore reacts vigorously. In one section where hydrogen peroxide was added, the bacteria did not bubble very strongly. In another area however, it did. If you added hydrogen peroxide to the same areas the next day, I think that the bubbling would still occur but not be as strong. Washing a cut out with hydrogen peroxide causes it to bubble because the same bacteria that were used in the experiment are the type of bacteria that are found in our bodies and in our cuts.

=Part 2: Lactase=

Phenol red lactose broth after incubation

After a period of time the red color has completely disappeared and the contents of the tube are bright yellow. There was a small gas bubble at the top of the smaller tube which indicates that the bacteria inside were releasing the gas as they grew. In the control tube none of this happened and there was no gas bubble because there were no bacteria growing at that time.

=Part 3: Cysteinase=

SIM medium after incubation period

There was no color change in the tube but there is some sort of white suspension in the middle of the tube. The combination of the cystein and iron atoms in the tube and the soil suspension that was added was the cause of the added suspension in the middle.

=Part 4: Protease=

Tube of nutrient agar after incubation period

There was no evidence of gas being produced in the tube. There were also no distinct colonies of bacteria that had formed with the agar. There really wasn't any evidence of bacteria growth at all.

=Part 5: Amylase=

Starch agar after incubation period

Starch agar after iodine was added

As can be seen in the second picture, there was no evidence of amylase on the agar plate since the iodine did not change color. Amylase production is a way for bacteria to obtain food while growing.

=Live Culture Pictures=

Bacteria magnified at 100x

Bacteria magnified at 400x

Yeast magnified at 100x

Yeast magnified at 400x