Nucleic acid Nucleic acid Nucleic acids are the biopolymers, or small biomolecules, essential to all known forms of life. The term "nucleic acid" is the overall name for DNA and RNA. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. If the sugar is a compound ribose, the polymer is RNA (ribonucleic acid); if the sugar is derived from ribose as deoxyribose, the polymer is DNA (deoxyribonucleic acid). Nucleic acids are the most important of all biomolecules. They are found in abundance in all living things, where they
N-Methyl-D-aspartic acid the latter is the only known endogenous antagonist. They are commonly referred to as NMDA receptor antagonists. N-Methyl-D-aspartic acid N"-Methyl--aspartic acid or N"-Methyl--aspartate (NMDA) is an amino acid derivative that acts as a specific agonist at the NMDA receptor mimicking the action of glutamate, the neurotransmitter which normally acts at that receptor. Unlike glutamate, NMDA only binds to and regulates the NMDA receptor and has no effect on other glutamate receptors (such as those for AMPA and kainate). NMDA receptors are particularly important when they become overactive during withdrawal from alcohol as this causes symptoms such as agitation and, sometimes,