dna extraction from strawberries
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DNA Extraction from Strawberries. Lab Safety and Tips. Wear Goggles Important to have clean glassware. Follow directions CAREFULLY or you will not get good results. I DNA. - PowerPoint PPT PresentationTRANSCRIPT
DNA Extraction from Strawberries
Lab Safety and Tips
• Wear Goggles• Important to have
clean glassware.• Follow directions
CAREFULLY or you will not get good results.
I DNA
• Single molecules of DNA are long and stringy. Each cell of your body contains six feet of DNA, but it's only one-millionth of an inch wide.
Chromosomes
• Strands of DNA molecules coated with protein
Start with a Strawberry
• Easy to pulverize• Already has
enzymes• Large genome
(lots of chromosomes)
Add Detergent
• Detergent/shampoo captures protein and releases DNA
Mashing Strawberries in a thick Ziploc bag
Careful!!
You don’t want Bubbles!DNA clings to the bubbles.
Salt
• The salt in the extraction buffer keeps the DNA molecules together and separates them from the protein.
Filtering the mixture will remove cell debris and organelles.
95% Cold Alcohol
• Alcohol separates the DNA from the other components of the cell
Note: slowly pouring down the side of the test tube
Good Tip
• Be careful to pour down the side of the container to form a layer on top instead of mixing the two layers.
ETHANOL MUST BE COLD!
• The DNA will rise into the alcohol layer and can be ‘spooled’ onto the wooden stick be carefully swirling the stick at the interface of the two layers.
DNA will look like snot
• White• Stringy• You are viewing • the DNA and protein
When DNA extractions are performed, you can expect three
basic results.
• No DNA • DNA appears fluffy which means
it has sheared in the extraction process
• DNA appears as thin threads.
Does you DNA look like this?
If not…Possible Errors
• Impurities could have easily been introduced during any step, which may have altered the outcome.
• Disturbing the solution as the DNA precipitated could cause poor results (probably due to the strands of DNA breaking up).
• Not allowing enough time for each step.