Purpose:
The purpose of this experiment is to classify the organisms present in the soil sample
Oberservations:
The organism that was found in the last lab was a rotifer but nothing else was found
Conclusion:
I am quite disappointed that there were no ciliates in my sample and I am wondering why there wasn’t any despite their hardiness.
Purpose:
To classify the ciliates that were found in last weeks sample. If people in your lab group don’t have any ciliates then they will be classifying whoever’s sample does have ciliates.
Materials:
Procedure:
Observations:
% sand: 68%
% silt: 9%
% clay: 22.7%
No ciliates were found in my sample of clay. However, when studying Camille’s sample, she didn’t have a ciliate either, but what we did find was a rotifer.
Conclusion:
no ciliates were present in my soil sample.
Purpose:
Understand and potentially discover and classify ciliates in our soil samples that we collected at the beginning of the year.
Materials:
Procedure:
Observations:
% water: N/A someone flooded my plate without my knowledge so this data was unobtainable
pH: 5.5
No ciliates were present
Conclusion:
This experiment didn’t work out quite as expected. Another participant flooded my plate without my knowledge so some sets of data couldn’t be collected. I had no organisms present in my soil either so there is no ciliate morphology to record.
Purpose:
The purpose of this experiment is to provide students with an opportunity to provide their data from the toxicity lab with the rest of the class and understand and compare the various results. Final figures were also presented and compared amongst each other.
Procedure:
Students created a final figure that tied all of their final data from their excel spreadsheet and presented it to the class. The figure had to have proper labels and could effectively present the results. This includes data for control-24hr and treatment-24hr (NH4Cl) testing on Tetrahymena.
Conclusion:
This was an important exercise because it taught students to present information to a large group of people while ensuring that visual aspects were correct. Everyone’s graph had the same kind of layout but there were differences that separated each one. When looking at overall results the class saw a decline in ciliates with a treatment of NH4Cl.
Introduction:
Today students will be analyzing their data that they put together on their statistical analysis spreadsheet, and will create a results graph that demonstrates the outcome of the experiment. This will be a basis for the results portion of the write up they will be submitting in the future.
Procedure:
Results:
The graph above shows that there is an effect on the population of Tetrahymena from 175mM of NH4Cl. The control group, which consisted of Tetrahymena and H2O, had a higher concentration of cells/ml, while the treatment group, which had Tetrahymena and NH4Cl, had a significant decrease in cell concentration.
Conclusion:
Students now have prepared a draft chart that will be used in the final lab report at the end of the unit. This activity provided them with practice on creating and analyzing statistical data, and coming up with conclusions.
Introduction:
In this experiment, students will be observing cultures of Tetrahymena. These ciliates are very easy to reproduce and contain a wide range of properties that make them ideal for microbial research. Throughout the rest of the semester, we will be using these ciliates to conduct our experiments. In today’s lab, students will get a hands-on experience with these organisms and will gain an understanding of how they behave, look, and practice how to use proper technique in looking at these creatures with a compound microscope.
Materials:
Procedure:
Observations:
4x Magnification:
10x Magnification:
40x Magnification:
Conclusion:
This provided students with a introductory experience with Tetrahymena, and they have now gained a better understanding of how these organisms are used in scientific research, and how to observe these creatures under the microscope.
Purpose:
This will allow students to understand how to organize their data on excel. They will practice a series of tests and analysis. Students will conduct descriptive analysis, create histograms, and perform an F-Test and a T-Test.
Activity:
4. After the statistical analysis has been performed, students will then create a histogram for each of the collected data. Before creating the histograms, students will need to create “bins” that will be used in the graphs. Be sure to create a histogram for Time 0, C-24hr, TRMT-24hr.
5. Students will be performing an F-Test that will be looking at 2 variables. We will be comparing the control data and the treatment data for this test. This test demonstrated that the data failed to reject the null hypothesis
6. Finally, we performed the T-test. This test also looked at two variables and those were the control 24hr and the treatment 24hr. This test also demonstrated that the data failed to reject the null hypothesis.
Conclusion:
Now students have been able to practice a series of analytical tests. This will beneficial for the research project that will be conducted for the rest of the semester. It is important that students have a firm grip of how to conduct these calculations and perform these analytical tests because the results will be based on the outcome of these.
Introduction:
The experiment was performed in in 12-24 well plates. Each well will have a final volume of 1000 ul, which includes the culture, treatment, and media. The plate should contain at least 3 treatment wells and 3 control wells.
Materials:
87.6ul of NHCl 912.4 of stock solution will be used for this used experiment
Serial Dilutions of the Stock Culture:
Baseline stock culture cell counts:
Students will use the dissecting microscopes to observe the Tetrahymena. Our group chose the 1:10 dilution factor. Next, we observed 10ul of our sample under a dissecting microscope. Then we took 3 10ul drops from the ideal solution and calculated the average number of cells/ml in the stock culture.
The concentration of New Tetrahymena Stock Culture:
To calculate concentration use the formula C1V1=C2V2
(1000)(350)=(4000)(ul)
Place 489ul of tetrahymena stock into a tube
Finally, fill the tube with PPT until it reaches 20ml.
Final Concentration:
The amount of NH4Cl we used was 87.6ul. We created 6 new wells. (3 control 3 treatment) and filled the treatment wells with 87.6ul of NH4Cl and 912.5ul of Tetrahymena. The control wells contained 87.6ul of H2O and 912.5 Tetrahymena. Next, we waited 24 hours and then came back and counted 3 10ul drops from each well. The averages of control wells and treatment wells were recorded.
Results:
Introduction:
In this lab, students will be performing cell counts, calculating cell concentration, and understanding the importance of serial solutions.
Brainstorming Experiment Ideas:
With my group, we discussed possible research formats. We decided that we would study the effects of various pH concentrations on Tetrahymena cultures. This would be applicable to the real world because many pollutants reach microbial systems, and since systems are crucial for life as we know it, it is important how we are harming or benefitting these organisms.
Micropipetting Activites:
This activity allowed students to understand why we use micropipettes and how to use them. Each student will put a drop of a 10ul, 100ul, and a 1000 ul drop onto a paper towel and compare the various sizes. The proper technique for this is to set the desired microliter, push to the first stop, insert micropipette into sample, release first stop slowly, then to apply taken sample, at a 45-degree angle, and push all the way to the second stop while making sure not to release the stops until you have removed the micropipette from the sample. Students will also need to perform a peer check that will include the following:
Serial Dilutions:
Serial dilutions are used to lower a number of ciliates per 10 ul. This allows the observer to better count the number of ciliates. Our group tried to observe the 5ul of stock culture with no dilutions, but the number of ciliates was too great to be observed. So we diluted the sample by a 1:10, 1:100, and a 1:1000 dilution factor. The only dilution that contained ciliates was the 10^-1 dilution which contained 8 cells per 5ul. The other dilutions contained no ciliates so that data was 0. After the data was collected, students used the formula cells/ml = (# of cells/# of ul) x dilution factor x 1000. We calculated that our average cells/ml in the undiluted sample were 160,000 cells.
Conclusion:
Students now have practiced serial solutions and calculating cell concentration. They have also learned to use the various tools that we will be using to conduct our research experiment for the rest of the semester.
Introduction
Students will gain a better understanding of the significance of dilution solutions, calculating solute concentrations. The basis for concentration calculations will be the formula C1V1=C2V2. In this formula, the C1V1 represent the initial concentration and the initial volume while the C2V2 represent the final concentration and final volume. Through simple algebra, the students will be able to determine certain variables through given data. Also in this lab, students will practice calculation cell concentration through observation a sample, calculate mean, median, and standard deviation.
Materials:
Activity 1:
In this activity, students will be counting a sample of Tetrahymena and from their observations will determine the cell concentration (cells/ml). The students should perform multiple trials to ensure consistent data, then they will determine the mean and Standard deviation. Our mean count was 9 cells. We calculated that our standard deviation was 0, but I believe that this was an error in our calculations.
Activity 2:
In this part of the experiment, students will be determining the actual cells/ml. The result can be calculated through the formula, cell/ml (# of cells/# of ul) x dilution factor x 1000. The reason why we divide the number of cells by the number of microliters is to determine the number of cells per microliter. Then we are going to multiply it by the dilution factor to find the number of cells in the stock, but you must also multiply by 1000 because that is how many microliters are in a milliliter. So using this formula for cell/ml we find that our cell concentration is 18,000 cells/ml.
Conclusion:
Students now have gained a better understanding of serial solutions, calculating cell concentration, and calculating the standard deviation and mean of data.
