How does a fish get air in water?

Answer 1

They absorb oxygen from the water through their gills kinda' like we get oxygen from the air with our lungs.

Answer 2

To the answerers who said that water is H2O, that's correct, but the fish can't break the bond between the hydrogen and oxygen to use this form. Otherwise, there wouldn't be any need to use airstones or filters to move the water around - they could just live in stagnant water.

Water contains a small amount of dissolved oxygen (extra oxygen in the water) and this is what's used. There isn't a lot, and it's measured in parts per million (ppm). Some fish can live in oxygen concentrations as low as 4 ppm, but most would prefer it to be 6-10ppm. Think of that amount of oxygen as 6 pennies out of one million to see just how small of an amount that is.

The dissolved oxygen gets into the water only at the water's surface. That's why if you try to keep a fish in a bowl (not a good idea!) they always seem to be at the surface gasping for air - none gets to the bottom of the bowl. To do this, you need something to circulate the water, either an airstone (which doesn't move that much of the water unless you have a very strong air pump) or a filter, which not only removes particles from the water, but causes the surface to "ripple". Once the oxygen is dissolved in the water, the fish can extract it by using their gills.

How much dissolved oxygen can be in the water depends on a number of factors - air pressure, water movement, water temperature (cool water holds more than warm), other substances that may be dissolved, and how many organisms are in the water that use it (this includes bacteriam worms, insects, tadpoles, and fish, as well as other aquatic organisms that take in oxygen directly from the water).

Answer 3

Water can dissolve oxygen in much the same way that it can dissolve salt or sugar or may other substances. The reason a fish tank needs to be aerated (the bubbly thing at the back of the tank) is to allow oxygen to dissolve into the water. I nature, this process occurs naturally over the large surface area of a river, lake or ocean, but in the aquarium, we need to help the process along because of the small surface area of the tank.

The fish passes that water over their gills, and the dissolved oxygen passes from the water to the fish's blood.

Answer 4

How Do Fish Breathe



How in the heck can a fish, which is underwater, breath if there is no air? When we go under water, we have to bring air with us to survive. Whales and dolphins have lungs that store air from the surface. Fish don't have lungs, and they rarely ever venture into the air, so how do they survive. We all know it has something to do with gills, but what exactly.

The water surrounding a fish contains a small percentage of dissolved oxygen. In the surface waters there can be about 5 ml. of oxygen per liter of water. This is much less than the 210 ml. of oxygen per liter of air that we breath, so the fish must use a special system for concentrating the oxygen in the water to meet their physiological needs. Here it comes again, a counter current exchange system, similar to the one we found in the fish's swim bladder and in the tuna's muscles.

The circulation of blood in fish is simple. The heart only has two chambers, in contrast to our heart which has four. This is because the fish heart only pumps blood in one direction. The blood enters the heart through a vein and exits through a vein on its way to the gills. In the gills, the blood picks up oxygen from the surrounding water and leaves the gills in arteries, which go to the body. The oxygen is used in the body and goes back to the heart. A very simple closed-circle circulatory system.

The gills: the gills are composed of a gill arch (which gives the gill rigid support), gill filaments (always paired), and secondary lamellae, (where gas exchange takes place).

:-)

Answer 5

Water absorbs oxygen at the surface, through the filter, or through a bubbler.

The fish sucks water into it's mouth and pushes it out through it's gills. During this transfer the fish absorbs the oxygen in the water.

Answer 6

Oxygen is dissolved in the water. The gills are a thin enough membrane for Oxygen and carbon dioxide to diffuse across. These gases move from areas of high concentration to areas of low concentration by diffusion. The pumping of the gills allows more water to come into contact with the membrane and the blood in a fish flows from tail to head while the water flows from head towards tail. This is called counter current exchange and allows more water to come into contact with more blood to increase efficiency.

Answer 7

Oxygen from the air dissolves in water and the fish pick up the oxygen in their gills. The exception is Battas and gouramis who also have a lung like organ in their head where they can breathe air.

Answer 8

They get air usually by a air pump that blows through a plastic tube with a airstone attached on the end which blows out small bubbles that contain oxygen and the fish breathes it in through their gills.

Answer 9

Water does contain oxygen but it doesnt necessarily need it as much as humans do, but when the water is low on oxygen, it goes to the top of the water and takes it from the air above the surface of the water.

Answer 10

Their gills force water into the mouth and out the gills, absorbing the oxygen in the water into their blood system.

Gills are lined with millions of blood vessels, much like human lungs.