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Fish "breathe" the dissolved oxygen out of the water using their gills. It turns out that extracting the oxygen is not very easy -- air has something like 20 times more oxygen in it than the same volume of water. Plus water is a lot heavier and thicker than air, so it takes a lot more work to move it around. The main reason why gills work for fish is the fact that fish are cold-blooded, which reduces their oxygen demands. Warm-blooded animals like whales breath air like people do because it would be hard to extract enough oxygen using gills. Humans cannot breathe underwater because our lungs do not have enough surface area to absorb enough oxygen from water, and the lining in our lungs is adapted to handle air rather than water. However, there have been experiments with humans breathing other liquids, like fluorocarbons. Fluorocarbons can dissolve enough oxygen and our lungs can draw the oxygen out.

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14y ago
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13y ago

they use gills to breath

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Q: How do fish breath in oxygen under water?
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Related questions

Why does fish breathe underwater?

fish breath under water because in water oxygen is mixed.

How do sea monkeys get oxygen?

they dont they are fish they breath under water

How do fish suit there environment?

Fish suit their environment because they can breath under water by extracting oxygen through their gills.

Do fish breath with lungs?

Fish use gills to extract oxygen from the water to 'breath' .

Where do fishes get oxygen when they breath?

fish have gills to breath so yeah

How the function of the gills is performed at shrimp?

Gills allow shrimp and fish extract oxygen from the water - therefore they can breath under water.

How do star fish circulate?

they breath in water and the oxygen from the water they take

Does algae in a fish pond contribute to the amount of oxygen in the water for the fish to breath?


Why there is oxygen in water but why is it that you cannot breath underwater but fish can?


Why can't a fish breath out of water?

gills-breath under water no gills-can't breath under water

How do fish breathe in water?

Most organisms, except for some such as anaerobic bacteria, respire oxygen. Fish have gills, gills have the ability to take the oxygen out of the molecule H2O.Fish have gills, which filter out the oxygen from the water. However, they can't breath out of water.A fish doesn't have lungs, it has gills, so it doesn't breathe in water really.Fish breathe under water by using their GILLSto surviveGills pull oxygen from the water but they can't breathe out of the water because the other chemicals in the air.

What do fish use their gills for?

Because they are underwater. They have to get oxygen that is dissolved in the water instead of that available in the air. Fish have an air bladder which controls their buoyancy. Some fish can use it as a lung. When they swim in the water they use their gills. When they are on land, they use their lung.