Science: DNA Extraction Experiment

 Hi there!

Today I will be writing about an experiment I conducted in Science.

Aim: 

To find DNA from Kiwifruit

Method: 

1. Mush half a kiwifruit (discard skin) in a ziplock bag with a splash of water and a small teaspoon of salt. 

2. Strain the solution through a cloth into a beaker.

3. Add a squirt of dishwashing liquid and stir.

4. Pour into a test tube.

5. Place the test tube in a beaker filled with WARM water.

6. Leave for 10 mins.

7. Slowly pour 5mL of methylated spirits down the side of the test tube. 

Results:

Discussion: 

Here is a diagram explaining:

An adult human can contain 50 trillion to 100 trillion cells, all of them (apart from red blood cells) contain a nucleus. A nucleus can be thought of as 'the control centre' of a cell, since it contains special instructions which tell that cell how to function. 

These instructions are positioned on chromosomes. Humans have 46 chromosomes in every cell in their body, one half (23) coming from the mother and the other half (23) coming from the father. 

DNA structure

Chromosomes are made up of DNA (deoxyribonucleic acid) molecules. A section of DNA gives instruction for specific characteristics. Hair colour is a good example of a characteristic, otherwise known as a gene. The scientific way of describing what DNA looks like is a 'double helix' however an easier way to remember is a twisted ladder. 

DNA is made up of simple repeating units which are called nucleotides. A nucleotide is made up of a sugar, a phosphate and a base.  Here is an example:

There are four different nucleotide bases which are found in DNA:

- Adenine (A)

- Thymine (T)

- Cytosine (C) 

- Guanine (G)

Since they are made up of different chemicals, not all of them are compatible with each other. An easy way to remember what bases go together is: Curly letters go together as do straight letters. This means that A and T go together and G and C go together. (Note: C and C cannot go together, same applies to G and G)

Conclusion:

I really enjoyed this experiment. I found it quite fascinating that the kiwifruit mixture separated into two sections after adding the methylated spirits to the test tube. Next time, something I think would be interesting to look at is the kiwifruit DNA under a microscope to see all the formations.

Thanks for reading!