Editing Nucleic acid sequence (section)

{{Short description|Succession of nucleotides in a nucleic acid}}
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{{DNA RNA structure}}
A '''nucleic acid sequence''' is a succession of [[Nucleobase|bases]] within the [[nucleotides]] forming [[allele]]s within a [[DNA]] (using GACT) or [[RNA]] (GACU) molecule. This succession is denoted by a series of a set of five different letters that indicate the order of the nucleotides. By convention, sequences are usually presented from the [[Directionality (molecular biology)|5' end to the 3' end]]. For DNA, with its double helix, there are two possible directions for the notated sequence; of these two, the [[Sense (molecular biology)|sense strand]] is used. Because nucleic acids are normally linear (unbranched) [[polymers]], specifying the sequence is equivalent to defining the [[covalent]] structure of the entire molecule. For this reason, the nucleic acid sequence is also termed the [[Biomolecular structure#Primary structure|primary structure]].

The sequence represents '''genetic information'''. Biological [[deoxyribonucleic acid]] represents the [[information]] which directs the functions of an [[organism]].

Nucleic acids also have a [[Nucleic acid secondary structure|secondary structure]] and [[Nucleic acid tertiary structure|tertiary structure]]. Primary structure is sometimes mistakenly referred to as "primary sequence". However there is no parallel concept of secondary or tertiary sequence.