Nitric oxide (NO) Nitric oxide (NO), colourless, toxic gas that is formed by the oxidation of nitrogen. Though it has few industrial applications, nitric oxide performs important chemical signaling functions in humans and other animals and has various applications in medicine.
or British mollusc /ËmÉËlÉsk/. plural mollusks. Learner's definition of MOLLUSK. [count] biology. : any one of a large group of animals (such as snails and clams) that have a soft body without a backbone and that usually live in a shell.
Characteristics of Mollusks. Mollusks are soft-bodied invertebrates with bilateral symmetry and usually one or two shells. Their organs are in a fluid-filled cavity; the word mollusks in Latin means soft.Most of the mollusks live in water but some live on land. There are more than 110,000 species that have been identified.A theoretical, idealized mollusk would crawl on a single flat, muscular foot, and the body would have at least a suggestion of a head at one end and an anus at the other.ost of the mollusks live in water but some live on land. There are more than 110,000 species that have been identified. A theoretical, idealized mollusk would crawl on a single flat, muscular foot, and the body would have at least a suggestion of a head at one end and an anus at the other.