Answer to Question #118963 in Zoology for Shania kumar

Question

Explain why some fish die if they are prevented from continously swimming forward.

Answer 1

Some species of fish, mostly sharks, like the mako and great white have to constantly swim to remain alive. All sharks take up water so they can breathe. Some cannot pump water over their gills but passively force water through their mouths and over their gills in a process called rum ventilation. In order to exchange carbon dioxide for oxygen, the sharks must continually pass water over their gills. Unlike most fish, these sharks lack the physical apparatus to manually perform the exercise. To stay alive, the sharks have to constantly swim foward. The process keeps water filtering through their gills in order to meet their oxygen demand.

Sharks that lack a swim bladder are negatively buoyant. Lack of a swim bladder makes the sharks sink when they are not swimming.