The building blocks from which DNA is made are known as deoxynucleoside-5′-triphosphates (dNTPs), which are made up of the familiar four DNA bases – Adenine, Guanine, Cytosine, and Thymine – plus a deoxyribose sugar and three phosphate groups. dNTPs are produced by the enzyme ribonucleotide reductase (RNR), and the enzymes that replicate DNA must obtain these molecules from the solution around them.
Imagine you have a tower of randomly coloured lego bricks, which you are trying to construct an identical copy of. The problem is that the materials you are using are not orderly arrayed on the floor but are instead being thrown at you randomly and must be caught before use. Continue reading