Strawberry DNA Extraction Lab

Poll

Do you think we can see DNA!?

• No, it's WAY too small

• What is DNA...?

• OBVI. Why else would we be doing this lab

Open Ended

DNA is what is responsible for our traits! It is what makes you, YOU! :)

If a strawberry is red, do you think that means it's DNA also has to be red? Be sure to include an explanation with your response!

​DNA Extraction

​Today our goal will be to see the DNA of a strawberry!

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However, in order to see the DNA of a strawberry, there are some barriers we need to get through in order to make that possible!​

The strawberry will be squished in a ziploc bag, in order to break the outermost barrier of the strawberry.

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Take a second to try and remember if you learned about this cell structure before!

Step 1 | CRUSHING the Strawberry​

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Multiple Choice

When squishing the strawberry, what barrier are we breaking down?

• Nuclear Membrane

• Cell Membrane

• Cell Wall

• Exoskeleton

Adding our fancy lysis solution (aka soapy water) will help us get through the next TWO barriers.

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These two barriers are known as lipid bilayers which will dissolve when coming into contact with our soapy solution.

Step 2 | Cell Lysis

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Multiple Choice

The cell lysis solution will allow us to break through the next TWO barriers. What are these barriers?

• Cell Wall and Cell Membrane

• Cell Membrane and Nuclear Membrane

• Nucleus and Nucleolus

• Cell Wall and Nuclear Membrane

DNA is spooled tightly around proteins (called histones), and we want to get it to unravel!

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Step 3 | Protein Digestion

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Poll

Which one of these do you think we can use to help release the DNA from the protein?

• Meat Tenderizer

• More Soap

• Tweezers

DNA is super teeny-tiny and we want to make sure we separate it from all of the massive chunks in the mess we've made.

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The cytoplasm, which is a jelly-like liquid, will be carrying the DNA. So we want to strain this liquid to separate it from the rest of the debris. So DNA is that tiny that it can slip on by!

Step 4 | Strain

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Holding our test tube at approximately a 45 Degree angle, we are going to slowly add ethanol.

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Ethanol causes the DNA to precipitate which means the DNA will begin clumping together and rising to the surface. Some gentle taps helps it to escape to the top layer of the mixture.

Step 5 | DNA Precipitation

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​Strawberry DNA!

Although it may not look like that images of DNA you are used to, this right here is Strawberry DNA!

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Strawberries are octoploid - meaning they have 8 sets of EACH chromosome. Whereas we only have 2 sets of each chromosome.

Now let's keep the fun going! Do you think you can see YOUR DNA?!?!?!

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