Question

Experiment 3: DNA Extraction 1. What is the texture and consistency of the DNA? 2. Why did we use a salt in the extraction solution? 3. Is the DNA soluble in the aqueous solution or alcohol? 4. What else might be in the ethanol/aqueous interface? How could you eliminate this? 5. Which DNA bases pair with each other? How many hydrogen bonds are shared by each pair? 6. How is information to make proteins passed on through generations? 7. Watch the Virtual Lab demonstrating DNA Extraction (located in the Student Portal and/or your lab introduction). In this experiment, how do the Lysis Solution and the Salt Solution vary by function? 8. Identify one step which was included in the Virtual Lab which was not required in the hands-on experiment. Then, identify one step which was included in the hands-on experiment, but not the virtual lab. Why weren’t these steps required?

Answer 1

1. What is the texture and consistency of the DNA?

The DNA seems to have a slimy and mucus like texture. The consistency is also very mucus like

2. Why did we use a salt in the extraction solution?

Salt makes the DNA less hydrophilic. Salt also helps to remove proteins that are bound to the DNA and keep them dissolved in the aqueous layer so they don't precipitate in the alcohol along with the DNA.

3. Is the DNA soluble in the aqueous solution or alcohol?

DNA is soluble in aqueous solution and less soluble in alcohol because alcohol is nonpolar and water is polar

4. What else might be in the ethanol/aqueous interface? How could you eliminate this?

Traces of RNA and DNA might be in the ethanol/aqueous interface.

5. Which DNA bases pair with each other? How many hydrogen bonds are shared by each pair?

Adenine pairs with Thymine = 2 Hydrogen Bonds

Guanine pairs with Cytosine = 3 Hydrogen Bonds

6. How is information to make proteins passed on through generations?

During cell division DNA replicates and the information in the DNA is passed on to the next generations