Cerevisiae Lab Report
If sodium chloride is added to a solution with Saccharomyces cerevisiae, then sodium chloride should hinder the growth and reproduction of those cells because the salt concentrations will limit the overall efficiency of the cell’s reproductive processes as well as decrease overall colony size. In our experiment, we plan to note the effects of salt on S. cerevisiae by both spot plating to note overall cell colony size and the number of total cells and through the use of electro photometry to also count total cell concentration.
Results:
In our experiment, we determined how the concentration of sodium chloride effected cell growth and proliferation. We allowed S. cerevisiae cells to grow in mediums of varying sodium chloride
concentrations …show more content…
This data was then pooled and averaged for each treatment and then used to determine the standard deviation and p-value of each treatment by a two-tailed T test. The control group exposed to 0.0 wt/vol of sodium chloride averaged 25.701 million cells/ml after 3 trials. The group exposed to 0.1 wt/vol of sodium chloride averaged 18.456 million cells/ml after 3 trials and showed no significant difference in total cells (SD = 8.239 million, p=0.537) when compared to the control group. The group exposed to 0.5 wt/vol of sodium chloride averaged 36.885 million cells/ml after three trials and showed no significant difference in total cells (SD = 10.024million, p=0.347) when compared to the control group. The group exposed to 1.0 wt/vol of sodium chloride averaged 36.188 million cells/ml after 3 trials and showed no significant difference in total cells (SD = 25.052 million, p=0.576) when compared to the control group (Figure 1).
Figure 1: The average number of cells per milliliter of S. cerevisiae present after 24 hours of growth in YPD medium mixed with various concentrations of sodium chloride (expressed …show more content…
One problem we encountered was counting live colonies on agar plates. We failed at doing this because either our initial S. Cervisie without NACL did not have cell growth in trial one or the YPD solution was contaminated in trial two. Another problem was that our spectrophotometer readings worked for trials 1 and 2, but failed for trial 3 because the sample dried out during incubation. Furthermore, spectrophotometer readings for trials four through six were successful but not statistically significant. Some possible sources of error include invalid spectrophotometer measures, the incorrect amount of absorbance of salt, dead yeast cells, contamination, plate overgrowth, and the yeast cells drying from being under the vent in the incubator. In the future, we can do this experiment more effectively by having more than three weeks to perform the experiment as well as letting the yeast grow for more than twenty-four hours. As a result of having a longer amount of time to do the study and letting the yeast grow for longer than twenty four hours, we would get better results; yeast multiplies and divides rapidly in a short period of time so having it do that for a long time would probably allow the yeast to increase its cell growth more. The significance of this experiment was that yeast is a model organism and it is found in both bread and beer. It is a universal organism
Results:
In our experiment, we determined how the concentration of sodium chloride effected cell growth and proliferation. We allowed S. cerevisiae cells to grow in mediums of varying sodium chloride
concentrations …show more content…
This data was then pooled and averaged for each treatment and then used to determine the standard deviation and p-value of each treatment by a two-tailed T test. The control group exposed to 0.0 wt/vol of sodium chloride averaged 25.701 million cells/ml after 3 trials. The group exposed to 0.1 wt/vol of sodium chloride averaged 18.456 million cells/ml after 3 trials and showed no significant difference in total cells (SD = 8.239 million, p=0.537) when compared to the control group. The group exposed to 0.5 wt/vol of sodium chloride averaged 36.885 million cells/ml after three trials and showed no significant difference in total cells (SD = 10.024million, p=0.347) when compared to the control group. The group exposed to 1.0 wt/vol of sodium chloride averaged 36.188 million cells/ml after 3 trials and showed no significant difference in total cells (SD = 25.052 million, p=0.576) when compared to the control group (Figure 1).
Figure 1: The average number of cells per milliliter of S. cerevisiae present after 24 hours of growth in YPD medium mixed with various concentrations of sodium chloride (expressed …show more content…
One problem we encountered was counting live colonies on agar plates. We failed at doing this because either our initial S. Cervisie without NACL did not have cell growth in trial one or the YPD solution was contaminated in trial two. Another problem was that our spectrophotometer readings worked for trials 1 and 2, but failed for trial 3 because the sample dried out during incubation. Furthermore, spectrophotometer readings for trials four through six were successful but not statistically significant. Some possible sources of error include invalid spectrophotometer measures, the incorrect amount of absorbance of salt, dead yeast cells, contamination, plate overgrowth, and the yeast cells drying from being under the vent in the incubator. In the future, we can do this experiment more effectively by having more than three weeks to perform the experiment as well as letting the yeast grow for more than twenty-four hours. As a result of having a longer amount of time to do the study and letting the yeast grow for longer than twenty four hours, we would get better results; yeast multiplies and divides rapidly in a short period of time so having it do that for a long time would probably allow the yeast to increase its cell growth more. The significance of this experiment was that yeast is a model organism and it is found in both bread and beer. It is a universal organism