it is filled with all kinds of air that can be found underwater.....
exaption
they have an organ called a swim bladder. It is filled with gas and it keeps them afloat.
A GAS FILLED ORGAN THAT HELPS STABILIZE THE FISH @ DIFFERENT DEPTHS OF THE WATER........... ur welcome
A GAS FILLED ORGAN THAT HELPS STABILIZE THE FISH @ DIFFERENT DEPTHS OF THE WATER........... ur welcome
The swim bladder can fill by gulping air at the surface, this enables the fish to float or empty by loosing air from the swim bladder through a pneumatic duct (a pneumatic duct is an internal gas filled organ) connected to the oesophagus, this enables the fish to sink. got this answer from another person. i really hope that it is right
The swim bladder is the organ that keeps the fish balanced and upright, is an internal gas-filled organ that contributes to the ability of a fish to control its buoyancy. It is also known as the gas bladder, fish maw or air bladder.
Fish have an gas-filled, internal swim bladder, whose buoyancy they regulate to keep from sinking or rising in the water.
Bony fishes use the swim bladder to help control and maintain their buoyancy. These are internally gas-filled organs which helps contribute the ability to stay at current water depth without wasting energy in swimming.
Helps maintain Fish buoyancy ( from further down in the water or to surface) The swim bladder can fill by gulping air at the surface, this enables the fish to float or empty by loosing air from the swim bladder through a pneumatic duct (a pneumatic duct is an internal gas filled organ) connected to the oesophagus, this enables the fish to sink.
swim bladder, large, thin-walled sac in some fishes that may function in several ways, e.g., as a buoyant float, a sound producer and receptor, and a respiratory organ. The swim bladder, or air bladder, is located in the dorsal portion of the body cavity and is filled with gases. When gas is added to the swim bladder, by diffusion through the blood vessels in the bladder walls, the fish becomes less dense overall; when gas is removed the fish becomes more dense. The addition and removal of gases is a mechanism by which the density of the fish can be made equal to that of the surrounding water at a given depth. The swim bladder produces sound by vibrating; these sounds are probably used in courtship. The organ also amplifies water-borne sounds and thus is an aid to hearing. In most fish the swim bladder has no connection to the digestive tract, but in some, such as the lungfish, there is a connecting tube leading to the pharynx, indicating that the organ may aid in respiration.
they die
Fish control their density with a gas-filled organ called a swim bladder. The average density of a particular fish's tissues, not including gas in the , is 1070 kg/m^3.