noun, plural: biomolecules
A biomolecule refers to any molecule that is produced by living organisms. As such, most of them are organic molecules. The four major groups of biomolecules include proteins, polysaccharides, nucleic acids, amino acids, DNA and RNA found in and produced by living organisms. Thus, many of the biomolecules are polymers. A polymer is a compound made up of several repeating units (monomers) or protomers and produced by polymerization.
A nucleic acid is a biomolecule composed of monomeric units of nucleotides. Each nucleotide, in turn, is comprised of phosphoric acid, sugar (5-carbon), and nitrogenous base. The chains of nucleotides in a nucleic acid are linked by 3', 5' phosphodiester linkages. Nucleic acids may be in the form of DNA or RNA molecules containing the genetic information important for all cellular functions and heredity.
A protein is a biomolecule composed of amino acids joined together by peptide bonds. Proteins are essential as they serve various biological functions: as a structural material (e.g. keratin), as enzymes, as transporters (e.g. hemoglobin), as antibodies, or as regulators of gene expression.
Carbohydrates are the most abundant among the major classes of biomolecules. Chemically, they are simple organic compounds that are aldehydes or ketones with many hydroxyl groups added usually on each carbon atom not part of the aldehyde or ketone functional group. They include monosaccharides, disaccharides, oligosaccharides, polysaccharides, and heterosaccharides.
Lipids are organic compounds that are readily soluble in nonpolar solvent (e.g. ether) but not in polar solvent (e.g water). Their major biological functions involve energy storage, structural component of cell membrane, and cell signaling.
Other biomolecules are metabolites and natural products. A metabolite refers to any substance produced by metabolism or by a metabolic process. Examples of metabolites are alcohols, amino acids, antioxidants, nucleotides, organic acids, vitamins, polyols, alkaloids, terpenoids, etc. Natural products include biologically-derived materials, bio-based materials, and bodily fluids.
- biological molecule
- biomolecular (adjective, of, pertaining to, relating to, or characterizing a biomolecule)