Question: I know DNA stands for Deoxyribonucleic acid but what exactly is DNA and what is its main purpose?

DNA is the biological instructions that make each and every species unique, and encodes for all the things that give the organism the ability to grow, survive and reproduce. DNA is found in all living organisms, and consists of a code. It consists of four nucleotides or bases – Adenine (A), Thymine (T), Guanine (G) and Cytosine (C). These four bases are stuck together in various combinations (known as as the DNA sequence) along a backbone made of sugar and phosphates in a long line. There is a second line of bases, and these match up to the bases on the other strand. The bases match to each other – A to T, and C to G. The bases match together, and end up wound up – what forms is known as a DNA double helix. It looks like this: http://lejeuneusa.org/wp-content/uploads/2010/09/dna-double-helix.jpg

In total humans have 6 billion bases of DNA, which make up our genome. The DNA helix is tightly wound up in our cells, and encodes for everything from our eye colour to liver cells to our immune system. In our case, DNA is inherited from our parents – we get half of our DNA from our mother, and half from our father.

So basically DNA is the code that makes us – well, us! The sequence of nucleotides (the As,Gs,Cs,Ts) dictates what will be produced. DNA is unzipped, ‘read’ by enzymes and turned into proteins – these proteins are the building blocks of different cells – some parts of the genome result in proteins that make up red blood cells, another part will encode for the proteins that make your brain cells and so on….DNA encodes for everything in our bodies, and all the processes going on in our bodies – it’s really quite impressive such a small molecule gives results inall living things on this planet!

DNA is very interesting and for further information have a look at this excellent website, that has more detail on what DNA is, and what its purpose is: http://www.genome.gov/25520880