Please answer all the questions answering only one question is not helpful :
Calculations on Multiple Stock Solutions—be sure to include the amount of water added and include all units
11. Calculate how to use the 1 M Tris and 0.2 M EDTA stock solutions to make the 400 ml of a of 10 mM Tris and 1 mM EDTA solution.
12. Calculate how to use a 3 M NaCl and 10% NP40 stock solutions to make a 500 ml of a 300 mM NaCl and a 0.2% NP40 working solution.
Calculations on Simple Dilutions—be sure to include the amount of water added and include all units
13. Calculate the volumes necessary to make 200 ml of a 1:5 dilution of a sample.
14. Calculate the volumes necessary to make 50 ml of a 1:8 dilution of a sample
15. Calculate how you would dilute a cell suspension containing 3,000,000 cells/ml to obtain 10 ml with 100,000 cells/ml
16. Calculate the volume of a cell suspension containing 800,000 cells/ml you would need to obtain a total of 250,000 cells
Practice Calculations on Serial Dilutions—be sure to include the amount of water added and include all units
17. Calculate and describe (or diagram) how you would use a 10% SDS solution to prepare a final volume of 20 ml of each of the following solutions: 8%, 4%, 2%, 1% 0.5%.
18. Calculate and describe (or diagram) how you would use a 5 M Tris solution to prepare 200 ml of each of the following solutions: 1M, 100 mM ,10 mM , 1 mM, 0.1 mM.
How much of the first dilution should you make to perform the following dilutions?
19. 300 ml of a 1:5 dilution
20. 100 ml of a 1:10 dilution
21. What is the minimum volume you should pipette with the following? (include units with your answers):
P2 P10 P20 P100 P200 P1000
22. How accurate was your pipetting?
23. Was it better with the larger volume or smaller volume pipettor? Provide rationale.
(If there was a consistent problem with one pipettor please tell the instructor.)
Standard Curves
24. Complete a standard curve for the data above and tape a printed version into your notebook.
25. What is the R-squared value of your trend line? Is this good or bad… i.e. would you repeat the assay?
26. What is the protein concentration of (Explain/show your calculations.)
Unknown #1 = Unknown #2 =
Data for DNA Concentration Procedure
Attach a labeled printout of the plate reader raw data as well as your generated standard curve to this lab.
26. What is the concentration of your unknown DNA sample?
27. What is the R 2 for your standard curve data? Why is it important that the R2 is >0.95?
28. Comment on the purity of your DNA... discuss- How can you determine the purity of DNA? What are common contaminants of DNA purified from cells?
