Is uracil a purine or a pyrimidine?  

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DNA and RNA are both known as nucleic acids. They are involved in allowing organisms to reproduce necessary components to stay alive and to pass on genetic information to the next generation.

Nucleic acids are polymers consisting of nucleotide sub-units.  A nucleotide consists of a nitrogenous base, a five-carbon sugar...

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DNA and RNA are both known as nucleic acids. They are involved in allowing organisms to reproduce necessary components to stay alive and to pass on genetic information to the next generation.

Nucleic acids are polymers consisting of nucleotide sub-units.  A nucleotide consists of a nitrogenous base, a five-carbon sugar and one or more phosphate groups. 

Nitrogenous bases consist of carbon rings. One type is called a pyrimidine. The other type is called a purine. Uracil, a nitrogenous base found in RNA, is a pyrimidine. Two other pyrimidines are cytosine and thymine. Thymine is only found in DNA. 

pyrimidine contains a six-member ring of carbon and nitrogen atoms. To contrast this, a purine consists of a six-member carbon ring which is attached to a five-member ring. They can be distinguished easily in a diagram from each other. The two purines are adenine and guanine.

I have attached a link with a diagram showing a pyrimidine and a purine to help visualize their differences.

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