2006-12-13 07:28:46 · 19 answers · asked by Jill 1 in Science & Mathematics ➔ Biology
You really mean, "why can't mammal lungs work under water?", and the answer to that is that mammals require a far higher oxygen uptake than fishes that survive on oxygen in solution in the water. In other words, mammals need more oxygen than any lung in water can extract, but fishes get along fine. It has nothing to do with lung "efficiency" in oxygen extraction.
The Wiki article explores the possibility of liquid breathing techniques for diving and medical purposes.
2006-12-13 07:32:23 · answer #1 · answered by Scythian1950 7 · 0⤊ 0⤋
The metabolic rates of animals that have lungs as their sole means of respiration are too high to be sustained by the paltry amounts of oxygen dissolved in water. (There are a few amphibians and fish that can breathe through their skin in air)
You'd need to have water continuously flowing in and out at a pace that would probably be destructive to delicate tissues. Probably be a catch 22 even if it didn't rip up the lungs, the extra effort involved would be enormous.
Respiring through lungs in air just involves trifling differences in a delicate balance of pressure in the chest and abdomen. Makes breathing a low cost expenditure for the body. Moving something that's hundreds of times more dense, like water, would require real constant effort.
2006-12-14 09:55:37 · answer #2 · answered by corvis_9 5 · 0⤊ 0⤋
Because air (which is what fills the lungs) has no volume and cannot repel the water. Once filled with water, the lungs fail to operate properly and it causes the person to drown.
2006-12-13 15:31:27 · answer #3 · answered by Meg...Out of Hybernation 6 · 0⤊ 0⤋
the exchange of oxygen to carbon monoxide is extremely fast thanks the the aveola in the lungs. the change from air (oxygen) if found in h2o (water) but the exchange if possible in the human lungs would take to long to seperate the water molecules and causing the excess of hydrogen left in our systems. (If) there was a way to make the exchange fast enough and produce a way for the loss of hydrogen out of the lungs also it could be plausible.
2006-12-13 16:00:13 · answer #4 · answered by Layla C 1 · 0⤊ 0⤋
Because they are unable to expellthe water that is inhaled. the water pockets in the aveloi and branches of the lungs and cause you to drown. Normally oxygen is changed into carbon dioxide and exhaled out in a gas form. Does this help?
2006-12-13 15:32:21 · answer #5 · answered by shellie t 2 · 0⤊ 0⤋
We are incapable of seperating the oxygen from the water, so when we try to breath it in our lungs fill with water. Fish have gills that take the oxygen out so they can breath underwater.
2006-12-13 15:58:24 · answer #6 · answered by Sandra H 1 · 0⤊ 0⤋
Unlike gills, lungs do not a "filter" in place to remove the oxygyn from the water.
Water in the lungs will actually prevent breathing from occuring.
Water covers the Villi (tiny capilaries used to take oxygyn in ) and does not allow them to aquire the needed oxygyn.
2006-12-13 15:33:26 · answer #7 · answered by wildcarrie777 1 · 0⤊ 0⤋
Seriously?
Our lungs do not have the ability to pull oxygen out of water molecules.
2006-12-13 15:31:29 · answer #8 · answered by chadmcasselman 2 · 0⤊ 0⤋
Because evolution changed them from fish gills to human lungs.
2006-12-13 15:32:53 · answer #9 · answered by markos m 6 · 0⤊ 1⤋
Because they cannot extract the oxygen from the water the way a fish can with its gills.
2006-12-13 15:30:41 · answer #10 · answered by Gene 3 · 2⤊ 0⤋