Composition and Organization
DNA is found in the nucleus of cells. It contains genetic codes that determine physical features. It contains deoxyribose which are nucleic acids.
DNA is a double stranded molecule which are connected by the nitrogen bases. Adenine can only pair with Thymine. Guanine can only pair with Cytosine.
Nucleic Acids of DNA
Consist of a sugar molecule attached to a nitrogen base and a phosphate group. There are 4 possible nitrogen bases...adenine, guanine, cytosine, and thymine.
Purines are double ring structures...Adenine and Guanine are purines which connect together. Pyrimidines are single ring structures...Thymine and Cytosine are pyrimidines which connect together.
Purines always bond with pyrimidines.