Colony 5 Lab Report

In which petri dish did you observe the highest hatching viability? Did the results support your prediction in Pre-Laboratory Question #2?

Next, aseptically add 20mL of T-soy broth and 2mL of late log phase of B. thuringiensis culture. Incubate this flask for 24 hours at thirty degrees Celsius shaking at 180rpm. The next time in lab, remove between 1 and 1.5 mL from the top of the tube that holds the soil using a syringe. Open a package of .22μm filter and place the syringe in the top of the filter and dispense the liquid into a centrifuge tube that is labeled as 100 and close the tube immediately. For the negative control, dispense 1mL of SM buffer into a microcentrifuge tube labeled negative control using a syringe. With four microcentrifuge tubes label them -1, -2, -3, and -4. Add 90 μL of SM to each tube, and then add 10μL of the 100 tube to the -1 tube and vortex. Then add 10μL of the -1 tube to the -2 tube and vortex. Keep this process going till the -4 tube. Next, dispense 50μL of the undiluted sample into .5 mL of B. thuringiensis and then vortex. Now mix in 5 mL of TA to the culture tube and pour onto a plate labeled 100 and let solidify. On a different plate, draw a grid with sections labeled negative control, -1, -2, -3, and -4. Aseptically add 4.5mL of TA with .5mL of B. thuringiensis by pouring and then pour onto the plate evenly. Let the plate sit for about ten minutes. After ten minutes transfer 5 μL of the negative control and the dilutions into the proper

Introduction: The biological membranes are composed of phospholipid bilayers, each phospholipid with hydrophilic heads and hydrophobic tails, and proteins. This arrangement of the proteins and lipids produces a selectively permeable membrane. Many kinds of molecules surround or are contained within

The oxidation number of an atom of any free element is ZERO. Means to say there is only one kind of atom present, no charge.

For the temperature test each bacteria was placed on a nutrient agar and incubated for either 10, 20, 30, 40, or 50 degrees Celsius for 48 hours. During the pH test, each organism was placed on four agars varying in pH level from pH 2, 4, 6 and 8 and incubated near 37 degrees Celsius for 48 hours. For the osmotic pressure test, each organism was placed on four agars one each containing 2%, 5%, 8%, and 11% NaCl concentration levels. These were incubated near 37 degrees Celsius for 48 hours. The results of the tests are recorded in Tables 1, 2, and 3. All tests were performed according to the instructions provided in Leboffe & Pierce(1). The biochemical tests used on both unknowns and the ubiquity are:

Station one: Station one shows that when a small piece of magnesium metal is placed over the flame of the Bunsen burner, the magnesium metal ignites, giving off a bright, white light. Once the flame has extinguished itself due to the lack of fuel, the magnesium metal turned from a metallic strip to a crumbled white powder. It can be decided that station one is a combination (redox) reaction, as a new product is synthesised by the combination of two reactants. The reactants, magnesium and oxygen gas in the air bonded together to form the product of magnesium oxide.

23. The color, colony size, and overall size altered at the end of the experiment.

The streak plate was a fundamental first test to isolate and grow a pure culture. The streak plate was incubated for 48hrs and grown at 37 degrees. The

Although the experiment was as fair as it could have been, there were some factors that were beyond our control. Firstly, the tubers that we used may not have been from the same specimen,

The objective of this experiment was to identify two unknown bacteria from a mixed culture. Which was done by using the aseptic technique which was very important to avoid any contamination and keeping the workspace clean while culturing bacteria for different tests. To start, I chose a tube which had a solution of mixed culture. I used the flame to sterilize the inoculating loop and dipped it into the tube and streaked for isolation on 2 TSA plates and placed them in an incubator at 37 for 24 hours. Next day I observed the growth of 2 different types of colonies one for each unknown on the two plates. So I picked the best one and labeled it as master plate and discarded the other plate. From the master plate, I subcultured each type of colony

Figure #2 This is a picture of our unknown in the oxygen requirement test. This organism is facultative/ Aero tolerant.

In the 10-3 pasteurized sample, the plate exhibited 71,000 cells/mL. The results of the additional dilution samples contained too few colony forming units to count. However, in the 10-7 dilution, although the plate demonstrated 12 colonies, there should have been no colony forming units on this plate. The reasons for this could have been that this sample was contaminated from “double-dipping” the sample before dispensing it onto the plate or when using the pipette, it mistakenly was inserted in a higher concentration sample and then immediately to a lower concentration sample before it was dispensed onto the plate.

Preparing serial dilutions of the alfalfa water will ensure an accurate count. The plates are incubated until you see visible colonies, usually 18-24 hours. The colonies you see growing on the plate are considered to have started from one viable bacterial unit but because bacteria are usually not found as individuals, the colony you see may have started from a single cell or a group of cells. The results are reported as colony forming units (CFU’s).

The decolorized Gram negative cells are stained pink. With the results from the Gram stain I was able to follow the “Unknown Identification Flowchart” to the next step, which was to prepare for the Starch Hydrolysis Test by inoculating a starch plate.

Half of each tube’s contents are poured into a new test tube each respectively after the tubes are incubated for 1 hour. One set of tubes is tested for: