According to Purdue University, nucleotides are used to construct nucleic acids, including DNA, tRNA, rRNA and mRNA. Nucleic acids are long polymers of nucleotides that store and transfer information and regulate processes within the cells of all life forms on Earth.
Three units comprise each nucleotide: a sugar, an amine and a phosphate. A nucleic acid polymer is formed when the phosphate and sugar components of adjacent nucleotides bind together to form the backbone of the polymer.
Nucleic acids are:
- Classified into two categories based on the sugar component of the nucleotides used to build them.
- b-D-deoxyribofuranose in deoxyribonucleic acid, better known as DNA
- b-D-ribofuranose in ribonucleic acid, or RNA
- Helical in Shape.
- DNA is composed of two strands of nucleotides that are bound together down the long axis of the molecule when the amine components of the nucleotides on one strand bind to their counterparts on the other strand. The resulting structure of the molecule is referred to as a double helix and resembles a ladder that has been twisted along its length.
- RNA consists of only one strand of nucleic acids and forms a single helix.
DNA stores the genetic material of an organism. The sequence of nucleotides along the DNA strands controls the sequence of amino acids added to the proteins as they are synthesized and plays a role in regulating which proteins are produced.
Several types of RNA transfer information within the cell and help regulate cellular processes.
- mRNA carries genetic information from DNA to the ribosomes — the protein synthesizing machinery of the cell.
- rRNA is a component of the ribosomes.
- tRNA transfers individual amino acids into place along growing protein chains.