DNA as the Blueprint

Instead of the book of life, DNA is more like the scrapbook of life. Sentences, paragraphs, or entire chapters are copied and haphazardly inserted into various parts of our genome. In some people, the same page repeats over and over, while other people don t have that page at all. 

The bases are extremely important to DNA. They can either be in the form of a pyrimidine (a six-member ring of carbon and nitrogen) or a purine (a six-member carbon and nitrogen ring attached to a five-member carbon and nitrogen ring). Of the two, the purines are larger. 

if a sequence of bases on one strand is A A G T C, the sequence of bases on the complementary strand must be 

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