{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

# Test 2 - 1 How would you prepare 750 mL of a solution...

This preview shows pages 1–2. Sign up to view the full content.

1. How would you prepare 750 mL of a solution consisting of 50 mM NaCl, 100 mM Tris, 15 mM EDTA, and 20 μ g/mL RNaseA? You have available to you stock solutions of 5 M NaCl, 2 M Tris, 1 M EDTA, and 50 μ g/ μ L RNaseA. Express your answers in the simplest form with the most logical units, and show all work for full credit. 2. You have run out of some DNA that you often use, so you go to the freezer to get your stock tube of nice, clean maxiprep DNA. Unfortunately, some of your label has rubbed off, and you can’t read the concentration. You remember that the concentration was relatively high, so you dilute 10 μ L of this DNA with 90 μ L of water, and then you take 5 μ L of this into 995 μ L of water in a quartz cuvet, and read the absorbance of this solution at 260 nm. You read an absorbance of 0.12. You remember that a 50 μ g/mL solution of double-stranded DNA will give an absorbance of 1.0 at 260 nm. What is the concentration of the DNA in your stock tube? Show all calculations for full credit.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern