Strawberry DNA lab Extraction
Purpose: The purpose of this lab experiment is to see if this particular type of fruit which in this case is a strawberry contains DNA. Using materials such as a Ziploc bag to help keep the entire strawberry in one place while it gets smashed and test tube to help better see the DNA and break down of the liquid in the left over strawberry sediments.
Background information: The long thick fibers of DNA store the information for the function of the chemistry of life. DNA is present in every cell of plants and animals. The DNA found can be extracted using common, everyday material. We will use an extraction buffer containing salt, to break up protein chains that bind around the nucleic acids, and dish soap to dissolve the lipid (fat) part of the strawberry cell wall and nuclear membrane. This extraction buffer will help provide us access to the DNA inside the cells.
Pre- Lab Questions:
1. What do you think the DNA will look like?
I think the DNA will look like tiny pink colored little things 2. Where is DNA found?
It is found in the nucleus
5mL DNA extraction buffer \soapy, salty water)
1. Place one good sized strawberry into a Ziploc bag.
2. Zip the bag up and smash or grind up the strawberry by pressing your fingers on the strawberry on the bag for 2 minutes. Careful not to break the bag!! 3. Pour the provided 10mLof extraction buffer (salt and soap solution) into the Ziploc bag. 4. Next mush the strawberry in the Ziploc bag again for another minute. 5. Assemble your filtration apparatus as shown at the top
6. Pour the strawberry slurry from the Ziploc bag and into the filtration apparatus by letting it drip directly into your test tube. 7. Slowly pour cold ethanol into the tube and OBSERVE the results. 8. Dip the loop or glass rod into the tube where the strawberry extract and ethanol layers come into contact with each other. OBSERVE. Data , Results, and Observations:
Calculations: There are no calculations that accompany this experiment Conclusion: In this experiment of the extraction of DNA from a strawberry we did find that a strawberry does in fact contain DNA. By pouring the ethanol into the test tube with the strawberry slurry we were able to see the DNA separate from both the strawberry slurry and ethanol while it floated to the top.
Post Lab Questions:
Match the Procedures and Functions for questions number 1-4 1. Filter strawberry slurry through cheesecloth
B. Separates components of the cell
2. Mush strawberry with salty/soapy solution
D. Break up proteins and dissolve cell membranes
3. Initial smashing and grinding of strawberry
C. Break open the cells
4. Addition of ethanol to filtered extract
A. To precipitate DNA from solution
5. What did the DNA look like?
The DNA looked most like a very clear, wet see through substance with many bubbles surrounding the inside and outside of it. 6. What happened in the final step when you added ethanol to your strawberry extract? The liquid strawberry separated into three parts. A red-pink liquid forms on bottom with a clear see through liquid on top and the bubbly, gooey, clear DNA floats to the top. 7. A person cannot see a single cotton thread 100 feet away, but if you wound thousands of threads together in a rope, it would be visible much further away . Is this statement analogous to our DNA extraction? Explain. Yes, this statement is analogous to our DNA extraction because like a single thread of cotton DNA is very hard to see alone but if you wound thousands of threads together like a strawberry it is more easily visible. 8. Why is it important for scientists to be able to remove DNA from an organism? It is important for scientists to remove DNA from an organism because it can be used to diagnose diseases or...
Please join StudyMode to read the full document