DNA (Deoxyribonucleic acid)
DNA, with it's ability to replicate and control life, is perhaps the most powerful substance on Earth
DNA (Deoxyribonucleic acid) |
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Replication
DNA replicates right before a cell divides. DNA replication is semi-conservative. That means that when it makes a copy, each new molecule would consist of one old strand and one new strand. This helps reduce the number of copy errors.
Genetic (biological) information is copied and eventually transferred from parent to off-spring. This is the phenomena of heridity. This can only happen if DNA replicates accurately.
How does it happen: Replication is performed by splitting (unzipping) the double strand of the DNA molecule down the middle via relatively trivial chemical reactions. It then recreates the "other half" of each new single strand by drowning each half in a "soup" containing the four bases.
Since each of the "bases" can only combine with one other base (the rules of complementary base pairing must be complied with), the base on the old strand, acting as a template, dictates which base will be on the new strand, since A always combines with T and C with G. This way, each split half of the strand plus the bases it collects or scavanges from the 'soup' which then fasten to the growing strand, will ideally end up as a complete replica of the original (unless a mutation occurs). So the genetic instructions can be passed from cell to cell and ultimately from generation to generation.
Enzymes are the machinery required to accomplish this DNA replication. In what has often been referred to as 'life's molecular dance' we have to admire and awe at the incredible choreography involved. There are various types of enzymes involved, each with their own seperate functions and responsiblies such as;
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