Extraction of DNA from kiwi fruit
1.
Peel your 1/4 kiwi fruit (don’t need the skin as the cells are mostly dead and do not contain DNA)
and cut into pieces
2. Mash up your kiwi fruit as much as possible using a pestle and mortar, or squash in a plastic bag
3. Take 25ml of the lysis solution (made by mixing 5g washing up liquid, 2g salt and 100ml tap water in
a beaker) This needs to be stirred slowly to prevent bubbles forming in the solution
4. Add the kiwi fruit to your mixture and mash up a bit more
5. Using a glass pencil, write your name on the beaker and put it in a water bath at 60 oC for 15
minutes
6. Whilst waiting answer the following questions:
a) Why do you mash the fruit before extracting DNA?
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b) What does the washing up liquid do?
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c) What does the salt do?
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d) Why do you think bubbles in the solution might be a problem?
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e) Why do we heat for 15min in a water bath?
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f) What is the purpose of the ethanol?
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7. After 15 minutes, remove the beaker and filter (filter paper and a funnel) into a clean new beaker
8. To extract the DNA you can either:

Add approx. 5-10ml of this solution to a test-tube and carefully pour an equal volume
of ice cold ethanol down the side of the beaker to form a layer on top of the kiwi
solution
OR

add approx. 5-10ml ice cold ethanol to a test-tube and carefully pour an equal volume of
the kiwi solution on top of the ethanol
9. Using a paperclip that has been straightened with a hook on the end, try to hook out the jelly-like
substance which is formed and place on a piece of card
g) Describe the DNA you have extracted from the fruit
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