Can You SeeStrawberries’

DNA?

Let’s Explore! What does DNA look like?

Make a model!Fruit Snacks = Base Pairs

Guanine – CytosineAdenine – Thymine

Rules =• G/C always go together• A/T always go together• Pick any colors to represent them• Stay consistent if you pick yellow/red

for GC, stay with it.

Toothpicks = Rungs on the Ladder. Carefully poke the toothpicks through your base pairs.

Twizzlers = Sugar phosphate backbone. Attach to ladder rungs. http://www.youtube.com/watch

?v=m-dQdq0LO2E

Now! Back to the Question!

Can you see Strawberry DNA?

Let’s try!

First – We’ll watch a video of some cool scientists who will show us a method for extracting DNA from a strawberry.

http://youtu.be/hOpu4iN5Bh4

Do you think you can do it?I know you can!

Here’s what you need!

1 ziploc bag½ cup of waterstrawberries frozen or very ripe fresh2 teaspoons of dish detergent1 teaspoon of salt2 plastic cupscoffee filterice cold rubbing alcohol (90%)stirring apparatus (popsicle stick or Qtip)

Team Up!

Get with a partner. Send a partner to collect your materials.

First

Add 2-3 strawberries to your bag.Zip and mush completely.

Second

Combine:½ cup water2 teaspoons dish soap½ teaspoon saltstir well

Third

Add:Soap solution to strawberry bag.Mix, but not enough to makea lot of bubbles.

Fourth

Filter:Pour the strawberry and soap solution into the cup THROUGH the coffee filter. Be careful!

Fifth

Pour:Pour an equal amount of the very cold alcohol into the cup of strawberry/soap solution. (This is really DNA in solution).

Sixth

Observe!

Strawberry DNA will appear! You did it! You did it!Use the Q-Tip to place it under the microscope if you like. Or you can spread it on the black paper and look at it through the lense. What do you see?