How come fish don't drown?

Answer 1

From howstuffworks.com

"An object immersed in a fluid (such as a fish or a person) experiences two major forces: the downward pull of gravity; the upward push of buoyancy.
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To ascend, a fish must reduce its overall density by increasing its volume without significantly increasing its mass. Most fish do this with something called a swim bladder.

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A swim bladder is just an expandable sac, like a human lung. To reduce its overall density, a fish fills the bladder with oxygen collected from the surrounding water via the gills.

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When the bladder is completely inflated, the fish has maximum volume and is pushed to the surface. When the bladder is completely deflated, the fish has minimum volume and sinks to the ocean floor."

You can read the complete article in the link.

btw, it was a good question...

Answer 2

Fish do not drown because of swim bladders. (Also known as gas bladder)
The gas bladder is a gas-filled sac located in the dorsal portion of the fish. It has flexible walls that contract or expand according to the ambient pressure. The walls of the bladder contain very few blood vessels and are lined with guanine crystals, which make them impermeable to gases. In physostomous gas bladders, a connection is retained between the gas bladder and the gut, allowing the fish to fill up the gas bladder by "gulping" air and filling the gas bladder through the pneumatic duct. In more derived varieties of fish, the bladder has a gas gland that can introduce gases (usually oxygen) to the bladder to increase its volume and thus increase buoyancy, termed a physoclistous gas bladder. To reduce buoyancy, gases are released from the bladder into the blood stream and then expelled into the water via the gills.

Answer 3

Well...... here's a little different way of looking at it...

Drowning is simply a way of suffocation. Suffocation is the lack of ability to breathe and/or absorb oxygen.

We can't breath in water and we "drown" because we can't move the water in and out of our lungs, and we cannot absorb the available oxygen from the water.

A fish out of water cannot absorb the oxygen in the air because it has no way to move the air over its gills as it does in the water, and if they could absorb the oxygen, they have no way to keep their gills moist enough to retain the capabilities of the gills. Therefore, they can't breathe the air as we do.

So because both cases cause suffocation due to exposure; either to air in one case, and water in the other, you could make a case of "drowning" for each situation.

My point: A fish out of water does drown!

JMHO lol

Answer 4

Some fishes can actually "drown" by not being able to come up for air. Anabantids (such as bettas) actually need to be able to come up to the surface to breathe air by using their labyrinth organ. Bettas which have been denied access to the water's surface have died, indicating that they are "obligate air breathers." Of course, they wont' survive out of water either.

Answer 5

They can't absorb oxygen from the air. A fishes gills are what lungs are to a human being. As water passes thru its gills oxygen is absorbed from the water.

Answer 6

Drowning= Not being able to get enough oxygen.

Fish have gills that they can breathe through.

Answer 7

They are well adapted to water. Only land animals drown. They dont have gills, they have lungs adapted to surface air instead.

Answer 8

That's because they breathe through their own gills which absorbs oxygen they need to breathe and survive.

Answer 9

Because all fish breath thorugh there gills.

Answer 10

They breathe the oxygen that's in the water.