When an object rests on a surface, such as a table, for example, the downward force it applies to the surface is counteracted by an equal but upwards force, or reaction, applied by the surface. See more at Newton's laws of motion. A response to a stimulus, such as a reflex.
Background. The northern snakehead fish (Channa argus) has been identified as an invasive aquatic fish across the country. Snakehead fish got their name because of their long, cylindrical body plan and large scales on their head that give them a snake-like appearance.
The northern snakehead is native to Asia and is one of 29 snakehead species. It made its national news debut in 2002, after an angler at a pond behind a strip mall in Crofton, Maryland, caught a long, skinny fish, about 18 inches from end to end, that neither he nor his fishing buddy recognized.he northern snakehead is native to Asia and is one of 29 snakehead species. It made its national news debut in 2002, after an angler at a pond behind a strip mall in Crofton, Maryland, caught a long, skinny fish, about 18 inches from end to end, that neither he nor his fishing buddy recognized.