Extracting DNA from strawberries practical:
Aim – Extracting DNA from strawberries.
Introduction:
The main purpose of the experiment was to extract DNA from a strawberry. Within the
experiment I used salt, water, detergent, alcohol, and strawberries. Through using DNA
extraction, the DNA can be used later on for other forms of investigation such as gel
electrophoresis or PCR tests. The main purpose of using detergent within the practical was to
help break down the cell wall and the nuclear envelope, as a result this would help to extract
the DNA from the strawberries.
The main purpose of salt within DNA extraction was to help the sugar phosphate backbone to
become neutralised (the charge). Through using salt, it would also help the DNA become more
hydrophobic compared to before and this would make it less soluble in water. This is important
as when the alcohol would be added, the DNA would separate from the rest of the mixture thus
allowing the DNA to be extracted.
Method:
1. I first started by taking the frozen strawberries and crushing them in order to produce a
mixture which I could use later on.
2. Once the strawberries had turned into a smooth mixture, I added 1 spatula of salt to the
mixture in order to help neutralise the charge of the DNA and make it less soluble in
water.
3. After adding the salt, I then added 4 drops of detergent to the mixture. This was
important as it would help to break down the cell wall and the nuclear envelope. I also
added a few drops of water in order to make it much easier for the detergent to be
mixed into the strawberries completely.
4. Once the water, detergent and salt was completely mixed in, I prepared my funnel
above my test tube and then poured my mixture into the funnel and pushed it through
into the test tube.
5. Once the mixture was pushed through into the test tube, I then pipetted approximately
1cm3 of alcohol. This then formed a layer above the strawberry mixture which then
helped me to clearly see the DNA which had become separated from the mixture.
6. Using the spatula, I then extracted the DNA.
Results:
, Gel electrophoresis practical:
Aim - using gel electrophoresis to separate different lengths of DNA fragments.
Introduction:
The main purpose of the practical was to be able to identify different lengths of DNA fragments
through separating them. Through using gel electrophoresis, the molecules of DNA could be
identified which could be used within other procedures. Within the experiment, I used
restriction endonuclease enzyme and the main purpose of this was to help with identifying
specific nucleotide sequences within the chain of DNA. I also used agar gels and the main
purpose of this was to help in separation of the nucleic acids. I also used buffer solutions and
loading dye and the main purpose of this was to provide ions which are essential for carrying
current through them, this would also allow the electricity from the power supply to pass
through them. In addition, the purpose of the loading dye was to assess the length that the
DNA fragments travelled within the gel.
Method:
1. I first started by mixing the sample of DNA with the enzymes and the loading dyes
within a beaker and ensured it was properly mixed together.
Aim – Extracting DNA from strawberries.
Introduction:
The main purpose of the experiment was to extract DNA from a strawberry. Within the
experiment I used salt, water, detergent, alcohol, and strawberries. Through using DNA
extraction, the DNA can be used later on for other forms of investigation such as gel
electrophoresis or PCR tests. The main purpose of using detergent within the practical was to
help break down the cell wall and the nuclear envelope, as a result this would help to extract
the DNA from the strawberries.
The main purpose of salt within DNA extraction was to help the sugar phosphate backbone to
become neutralised (the charge). Through using salt, it would also help the DNA become more
hydrophobic compared to before and this would make it less soluble in water. This is important
as when the alcohol would be added, the DNA would separate from the rest of the mixture thus
allowing the DNA to be extracted.
Method:
1. I first started by taking the frozen strawberries and crushing them in order to produce a
mixture which I could use later on.
2. Once the strawberries had turned into a smooth mixture, I added 1 spatula of salt to the
mixture in order to help neutralise the charge of the DNA and make it less soluble in
water.
3. After adding the salt, I then added 4 drops of detergent to the mixture. This was
important as it would help to break down the cell wall and the nuclear envelope. I also
added a few drops of water in order to make it much easier for the detergent to be
mixed into the strawberries completely.
4. Once the water, detergent and salt was completely mixed in, I prepared my funnel
above my test tube and then poured my mixture into the funnel and pushed it through
into the test tube.
5. Once the mixture was pushed through into the test tube, I then pipetted approximately
1cm3 of alcohol. This then formed a layer above the strawberry mixture which then
helped me to clearly see the DNA which had become separated from the mixture.
6. Using the spatula, I then extracted the DNA.
Results:
, Gel electrophoresis practical:
Aim - using gel electrophoresis to separate different lengths of DNA fragments.
Introduction:
The main purpose of the practical was to be able to identify different lengths of DNA fragments
through separating them. Through using gel electrophoresis, the molecules of DNA could be
identified which could be used within other procedures. Within the experiment, I used
restriction endonuclease enzyme and the main purpose of this was to help with identifying
specific nucleotide sequences within the chain of DNA. I also used agar gels and the main
purpose of this was to help in separation of the nucleic acids. I also used buffer solutions and
loading dye and the main purpose of this was to provide ions which are essential for carrying
current through them, this would also allow the electricity from the power supply to pass
through them. In addition, the purpose of the loading dye was to assess the length that the
DNA fragments travelled within the gel.
Method:
1. I first started by mixing the sample of DNA with the enzymes and the loading dyes
within a beaker and ensured it was properly mixed together.
