Skin, brain, eyes, nose, mouth and throat, heart and blood, skeleton, lungs, the digestive system...the human body is a collection of organs and systems, which work together and make life possible. The most fundamental unit of the body is the cell, which we are able to observe and study, but not replicate. Although all the ‘ingredients’ to build a human being can be found relatively easily, we are still not able to recreate the miracle of life. Several experiments have attempted to calculate how much it would cost to create a body: the Royal Society of Chemistry, for example, estimated in 2013 that it would cost just under one hundred thousand pounds to recreate a human being using the actor Benedict Cumberbatch as a model. Just one year earlier, on an American television programme, this figure was estimated to be $168. Overlooking this astounding difference between these two estimates for a moment, the elements needed to create a human being, such as hydrogen, oxygen, nitrogen, carbon, selenium, and so on, are readily accessible; the difficult thing is understanding how to transform them into a living being that contains seven billion billion billion atoms.
Everything about the human body is controlled by DNA, which contains the genetic instructions that determine our physical appearance, and creates the proteins needed for each process. Its job is to duplicate itself to produce more DNA and pass on information from generation to generation: the chain of DNA in those of us alive today has never been broken since the appearance of humans some three billion years ago. DNA is imperceptible in size, but if we were to stretch out the entire length contained in each cell of the human body, it would cover the distance from Earth to the planet Pluto.
