Monthly Archives: October 2013

famous molecule



Let’s face it, DNA is the most famous molecule in the world as we know it. We don’t even have to mention its full name – deoxyribonucleic acid – and we only have to see a double helix to know what we are talking about..

DNA is not a simple compound like salt which is always sodium chloride, a compound of two atoms stuck together in the NaCl molecule.  DNA molecule is a format for storing information in chemical form. DNA is the nucleus in each of our cells – let’s say in the flesh of our finger tip – is a series of long molecules, twisted around proteins called histones that act like a set of spindles for the DNA.

Each chromosome is a single molecule of DNA with its accompanying histones, and each of our cells contains 46 chromosomes in the cell nucleus. The important thing is that the DNA in each cell is a single molecule. This is not obvious because they are wrapped up in a bundle, making it more chunky than a typical molecule. The DNA molecule in human chromosome 1 is the largest molecule in the human body, with 10 billion atoms in it – staggering to even imagine.

The double helix structure of DNA is very similar to a spiral staircase. The helix pasrt consists of a long string of sugars, backbone polymers, long chains of atoms with a repeating structure. As far as the DNA is concerned, these are just foundations. The important constituents are the treads of the special staircase. Each tread is made up of a pair of chemical compounds, which are selected from the four bases: cytosine, guanine, adenine and thymine. Those four bases CGAT are like the zeros and ones in binary code in a computer, and there are six billion base pairs in the DNA that is found in each of our cells.

It is those codes that store the information that will be used to produce various proteins, the multi-purpose workers of the biological world, and to create a whole set of other molecules that help determine how we are formed and develop over time. So you can see why DNA is described as the blueprint for the living thing that contains it. The 46 molecules of DNA in the nucleus of a cell start from a single cell and eventually the cell keeps dividing until reaching our current total of about 50 to 70 trillion cells in the human body.