Effects of Pantothenic Acid on the Growth of C.neoformans Essay

1) Make a pie chart – and figure out if 360O of the piechart represented 24 hours – 1440 min. how long did the cell spend in each phase? (Interphase to cytokinesis).

In this experiment first the stages of an onion cell undergoing mitosis are going to be observed and every stage is going to be detected and drawn on paper. A brief description to what is going on should be attached to the pictures. This is important to understand the basics of cell division which is necessary growth,repair and asexual reproduction. Second the number of cells undergoing each phase is going to be counted to figure out in which phase the cell remains the most. If interphase is the stage in which the cell grows and prepares for cell division then the

Purpose: The purpose of this lab was to calculate the amount of time that was spent by a cell in each of the phases of mitosis. Also, it is used to be able to compare the process of mitosis between plant and animal cells.

In the beginning of lab, we were advised to obtain a nutrient agar petri plate, which is used for the cultivation of microbes supporting growth of non-fastidious organisms. Since it contains many nutrients, a wide variety of bacteria and fungi can grow. Taking the plate,

(Biology Dept.). 0.1 ml of E.coli K or 0.1ml of E.coli B was added to the 10 fold dilution. Using soft agar technique, the growth media mixture with E.coli was plated and incubated.

Cytoplasmic streaming was measured 4 times after flushing the cells with pond water, at 5 minute intervals

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:

10. Now, calculate the percentage of the cell cycle spent in each phase and record it in Data

This experiment can be enhanced in many ways. The amount of alcohol used as treatments could be lessened to measure the viability of A. salina more accurately. The amount of cysts in each Petri dish was not consistent because there

The solution has been dechlorinated and adjusted to be slightly acidic. Place 75 mL of the solution in each of three labeled beakers. Obtain an animal organism, small fish, and a plant organism, Elodea. One beaker will be the control and will not have anything in it. Place exactly 25 mL of water in a 50-mL graduated cylinder. Place each organism in a cylinder and note the increase in volume above the original 25mL. The increase equals the volume of the organism. After taking measurement, cover each beaker with the plastic film. Place the beaker containing the Elodea in the dark by covering it with aluminum foil. Allow organisms to respire for 15 min. Gently remove the organisms from the beakers and return them to their original culture bowls. Then add four drops of phenolphthalein to the contents of each beaker. The solutions should remain clear because the solutions are acidic. Using a dropper bottle, dispense NaOH into the contents of the beaker drop by drop. Thoroughly mix the contents of the beaker after adding each drop. Continue adding drops until you first notice that the solution turns pink. Repeat for each beaker with at the living organism until the solution is the same shade of pink as the

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.

This experiment is about bacterial growth. We will demonstrate a bacterial growth curve using a closed system. Bacterial growth usually takes up to 12-24 hours to get an accurate result so we will be monitoring this growth between two classes. We also used different methods to determine bacterial growth as well as a few different calculations. One way of receiving data is by using a spectrophotometer where we will record the absorption at a given time to create the bacterial growth curve. We also used the plate count method after performing a serial dilution to calculate the actual cell density at different times given. By using this method we can count the population number of the same given and see the maximum cell density

Before plating the strains on agar plates, dilutions of the three strains of cells were prepared with LB broth.

The cell suspension in PBS was taken and mixed with an equal volume of 0.5% Trypan blue (Biosciences). A drop (10l) of the Trypan blue/cell mix was applied to a hemocytometer. The unstained cells (viable) and stained cells (nonviable) were counted.

A sterile pipette was used to add 0.1ml of E. coli culture to the pH 3.0 tube. This was then repeated for the tubes at pH 7.0 and pH 9.The tubes were then incubated at 37oC for 48 hours. This was then repeated for saline culture of Saccharomyces cerevisiae but incubated for 72 hours at 25oC.