P12 DNA

OBJECTIVE

We want to reveal the presence of DNA in aliments like kiwis and bananas and we also want to know the procedure to extract it.

MATERIAL 

• Test tubes
• Paper filter
• A funnel
• Graduated cylinder
• Erlenmeyer
• Beaker 600 mL
• Spatula
• Pipette
• Mortar and peatle. 
• Microscope
• Weighing machine
• Freezer
• Commercial soap for washing the dishes (FAIRY)
• Distilled water
• Ethanol of 96º
• Sodium chloride 2M
• A Banana
• Pineapple juice
• Strainer
• Acetic orcein

PROCEDURE

We can use either a kiwi or a banana, the procedure is exactly the same.

• Take the ethanol and put it on the freezer so that it can be cold.

• Weigh 100 g of banana in a weighing machine and crush it until it has taken the form of porridge.  

• Prepare a solution of 3g of Sodium chloride, 100 mL distilled water and 10 mL of the commercial soap in 600Ml Beaker and add the porridge inside the beaker.
• Mixed everything and then get another 600mL and strain the porridge, to make it juice, then you can throw away the rest.
• Prepare a graduated cylinder, with a funnel and filter paper inside and strain the juice again, we only need 5mL, we add 1 Ml of pineapple juice in.

• Then we put 6 mL of ethanol inside and mix it with a spatula slowly.
• Deposit the DNA strands in a slide and add some drops of acetic orcein and left it for 5 minutes.
• Wash the preparation with distilled water, dry and then cover it with a coverslide.  

RESULTS

CUESTIONS

How can you release DNA from the surrounding membranes?
The soap break down cell membranes and release DNA.

Why do we use Pineapple juice? Because it contains an enzim that destroys the proteins of the DNA molecular. 

How do we get the precipitation of DNA dispersed? With ethanol, it precipitates DNA strands and join the in a clum.