Levels of Structure in Nucleic Acids

In Chapter 4, we identified four levels of structure—primary, secondary, tertiary, and quaternary—in proteins. Nucleic acids can be viewed in the same way. The primary structure of nucleic acids is the order of bases in the polynucleotide sequence, and the secondary structure is the three-dimensional conformation of the backbone. The tertiary structure is specifically the supercoiling of the molecule. 

There are two principal types of nucleic acids, DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). 

The primary structure of nucleic acids is the order of bases. The secondary structure is the three-dimensional conformation of the backbone. The tertiary structure is the supercoifing of the molecule. 

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