Please Clarify

[fire]

fish have a gas-filled organ known as swim bladders that allows a fish to maintain buoyancy and balance in the water is it actualy gas or is it air im really confused by it. mostly i think air but would really like to know

[eifionlewis]

Well air, by definition, is gas, however the gas inside a swim bladdder of a fish is not the same as air. Swim bladders are regulated by the relationship between pressure and gas solubility. Basically by increasing the concentration of solutes in the blood going into the swim bladder, the pressure of the blood increases and gas comes out of solution, filling the bladder. As fish move through various depth changes, fish also need to get rid of some gas from time to time, and this occurs by the concentration of solutes in the blood being reduced, thus reducing the pressure, and gas moving into solution. The main gasses utilised in this way are (i think) nitrogen and oxygen, among other gasses, so the gasses used are possibly the same as air, but not in the same proportions.

[eifionlewis]

Well air, by definition, is gas, however the gas inside a swim bladdder of a fish is not the same as air.

Its been a few years since i studied this, but i'll give it my best shot! Swim bladders are regulated by the relationship between pressure and gas solubility. Basically by decreasing the concentration of solutes in the blood going into the swim bladder, the pressure of the blood decreases and gas comes out of solution, filling the bladder. As fish move through various depth changes, fish also need to get rid of some gas from time to time, and this occurs by the concentration of solutes in the blood being increased, thus increasing the pressure, and gas moving into solution.

Think of a soda bottle, when you open the bottle, the pressure on the soda decreases, and carbon dioxide bubbles come out of solution.

The main gasses utilised in this way are (i think) nitrogen and oxygen, among other gasses, so the gasses used are possibly the same as air, but not in the same proportions.

[eifionlewis]

Sorry ignore my 1st answer, i got it the wrong way round!!! If you can find a way to delete it please do!!