The nucleic acids are very large molecules that have two main parts. The backbone of a nucleic acid is made of alternating sugar and phosphate molecules bonded together in a long chain. These molecules carry genetic information or form structures within cells. The most common nucleic acid is Deoxyribonucleic acid (DNA), or ribonucleic acid (RNA). DNA is often compared to a set of blueprints, since it contains the instructions needed to construct other components of cells, such as proteins and RNA molecules. There is also nucleic acids in viruses. Even though there are four different nucleotide bases that can occur is each nucleic acid, there are millions of bases bonded to it. These bases act as a genetic alphabet on which the structure of each protein in our bodies is encoded. These 4 different bases that are in DNA are adenine (A), cytosine (C), guanine (G), and thymine (T).
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These bases are mostly found in DNA, while in RNA uracil replaces thymine. RNA is a nucleic acid, consisting of many nucletides that form a polymer. Each nucleotide consists of nitrogenous base, a ribose sugar, and phosphate. RNA is similar to DNA, but there are some differences between the 2. RNA is usually single stranded, while DNA is usually double stranded.external image NA-comparedto-DNA_thymineAndUracilCorrected.png