Our Own Slice Of Immortality; The Extraction and Precipitation Of Our DNA

A) For all living  organisms DNA is present, and for some, DNA is the code for life. However, not until fairly recently have scientists known DNA's genetic importance. In human beings DNA codes for such traits as hair color, eye color, height, facial features and blood type. In 1953, James Watson, Francis Crick and discovered the structure of DNA with the help of Rosalind Franklin. The scientists built a model of DNA, which was the first accurate model of its time. Their model described that DNA a double helix, connected by four nitrogenous base pairs, adenine, thymine, guanine, and cytosine. Each base is connected to a sugar and a phosphate group, which act as the backbones of the structure. The entire unit is called a nucleotide. The DNA of the cell is found in the nucleus of almost every cell of the human body (because an enzyme called DNASE evolved to kill all DNA outside of the nucleus in case the DNA was viral). The DNA is coiled up around histones (proteins) and organized into structures called chromosomes. There are 46 chromosomes in human cells, and all of the genetic information contained in the 46 chromosomes represents the genome. A gene is a section of DNA which codes for a certain trait. Humans receive their DNA from their parents, half from the father, and half from the mother.

B) The purpose of this experiment is to precipitate our own DNA. Precipitating our DNA will make it visual, and we will have the chance to view our very own DNA. This allows us to compare it, and would allow us to test it, clone it or sequence it.

C) To precipitate our DNA, the first objective we must complete is to extract our cheek cells by rinsing our mouths vigorously with a 0.9% saline (isotonic) solution. The solution will allow for quick extraction, and the cells will not burst in an isotonic solution. We will then add the lysis buffer (soap), and invert the tube several times to mix in the buffer completely. The lysis buffer will break open the cell membrane by dissolving the phospholipids in the plasma membrane. After the addition of the buffer, protease will be added and the tube inverted to spread the Protease throughout the test tube. Protease had the purpose of destroying DNASE before DNASE can kill our DNA. DNA has a negative charge, and water has a positive charge. Because of this, DNa is hydrophilic (attracted to water) and will dissolve in water. To counter this, we will add salt which will neutralize DNA's charge. Without a negative charge, DNA will become hydrophobic and non-polar. Our DNA will then be placed in a hot water bath to speed up the reaction time and break open the cell membrane. To finish this process we will add cold ethanol to precipitate the DNA. Ethanol is the preferred substance because of it's lower freezing point. It will become colder while staying a liquid.