English Deutsch Français Italiano Español Português 繁體中文 Bahasa Indonesia Tiếng Việt ภาษาไทย
All categories

2007-01-28 18:59:05 · 2 answers · asked by adrianbernardo 1 in Science & Mathematics Chemistry

2 answers

I have to take strawberry as the object you are extracting from.
1. Take 2 strawberries with their leaves removed, place them inside a zip-loc bag. Seal the bag tightly and trap as little air as possible.
2. Squeeze and mash the strawberries within the bag until it becomes an almost liquid mixture. Use your fingers but do not tear the bag.
3. Add 25cm3 of the extraction buffer to the strawberry mash. Remove the extra air and resealthe bag and squeeze mixture for another 2 mins.
4. Put a piece of filter cloth over a filter funnel and then place the filter funnel in a test tube.
5. Cut a hole at the bottom of the bag and pour the mixture into the filter funnel. Allow the red liquid to drain and drip into the test tube.
6. Once the test tube is about 1/4 filled with the red liquid, transfer the filter funnel to another test tube for it to drip.
7. Tilt the 1/4 filled test tube and slowly use a dropper to add 2cm3 of chilled ethanol down the side of the tube. The ethanol should form a layer above the red liquid.
8. You will observe a pale layer at the interface of the 2 liquid phases. Use a satay stick to dip between the 2 layers and slowly pull out the whitish material and a long stringy thread will follow. The stringy thread is the extracted DNA, which you can isolate and keep aside.

Extraction buffer: 1/2 teaspoon sodium chloride, 1 tablespoon detergent, 1/3 cup of water- kept in an ice box

The process works this way: DNA can first be released by breaking the physical membranes (nuclear and cell membranes) which is the strawberry itself. Removing the proteins that bind them into the chromosomes can be done by adding the extraction buffer. Isolation of DNA involves both chemical and physical means because membranes are made of lipids and proteins.

Hope this helps. I do know it doesn't work with banana, that's all.

2007-01-28 19:20:21 · answer #1 · answered by Memyselfi 4 · 0 0

during mitosis when the DNA begins to bundle into chromosomes it can be seen under a microscope. Then the DNA can be extracted and a number of different methods can be used to determine the actual sequences that make up DNA

2007-01-28 19:04:14 · answer #2 · answered by darcy_t2e 3 · 1 0

fedest.com, questions and answers