Physiology of Finfish and Shellfish (2+1)

2.4.4. Regulators and conformers

Two major types of osmoregulation are osmoconformers and osmoregulators. Animals whose internal osmotic concentration is the same as the surrounding environment are considered osmoconformers, whereas those that maintain an osmotic difference between their body fluid and the surrounding environment are referred to as osmoregulators. Most of the invertebrates among marine animals are osmoconformers whereas most vertebrates are osmoregulators.