Glossary | N

Nauplii
first free-swimming larval stage of many crustaceans including copepods, ostrapods and decapods
Nauplius
first free-swimming larval stage of many crustaceans including copepods, ostrapods and decapods
Nekton
pelagic (open ocean) animals that are able to swim against ocean currents
Nematocyst
specialized stinging cells; also called cnidae, in jellies, spirocysts, and plychocysts in anthrozoans (sea anemones, corals, sea pansies, sea pens). Used for capturing prey and/or defense from predators.
Neritic zone
nearshore area. The area of the ocean that lies along the coasts of continents and islands, less than 300 meters below the surface.
Neuromasts
groups of sensory cells in the lateral line of fishes
Neuromuscular
pertaining to both nerves and muscles
Neurotoxin
toxin that acts specifically on nerve cells, commonly causing paralysis that acts specifically
Neutral buoyancy
weightless in water, neither rising or sinking
Niche
ecological role of an organism and its position in the environment
Nocturnal
active at night
Noxious
harmful to living things
Nudibranch
sea slug; a marine gastropod without an external shell and mantle
Nutrient
any of a number of inorganic or organic compounds or ions that promotes growth or provides energy