DNA DNA Deoxyribonucleic acid (; DNA) is a molecule composed of two chains that coil around each other to form a double helix carrying the genetic instructions used in the growth, development, functioning and reproduction of all known living organisms and many viruses. DNA and ribonucleic acid (RNA) are nucleic acids; alongside proteins, lipids and complex carbohydrates (polysaccharides), nucleic acids are one of the four major types of macromolecules that are essential for all known forms of life. The two DNA strands are also known as polynucleotides as they are composed of simpler monomeric units called nucleotides. Each nucleotide is composed
Citric acid ingredients in the production of antiviral tissues. Citric acid is used as an odorless alternative to white vinegar for home dyeing with acid dyes. Sodium citrate is a component of Benedict's reagent, used for identification both qualitatively and quantitatively, of reducing sugars. Citric acid can be used as an alternative to nitric acid in passivation of stainless steel. Citric acid can be used as a lower-odor stop bath as part of the process for developing photographic film. Photographic developers are alkaline, so a mild acid is used to neutralize and stop their action quickly, but commonly used acetic acid leaves