Why are gills not suitable for breathing air?
Gills are designed to absorb oxygen only from water, and can
only work if water is passing through them or they will collapse.
When a fish is taken out of the water, the oxygen-absorbing
filaments of the gills flatten out and the fish suffocates because
it's gills are not made to absorb oxygen directly from
The simple answer is that gills colapse when removed from water as they are adapted to water which is more dense than air.
In air breathing animals, the lings are the organ system that takes in air and extracts oxygen for distribution through the circulatory system. In water breathing animals, the gills perform this function. Those smaller animals that have neither lungs nor gills usually have a system for direct absorption of oxygen from the air, or water.
A young baby frog is a tadpole. A tadpole is adapted to live in water. For breathing, it has gills, which helps it remain inside water until it grows up to become a frog. Gill are breathing organs of fish also, and the mode of living of a tadpole is similar to that of a fish. When it becomes a frog, it is capable of breathing both in air and in water. For breathing in…
The animal world is basically divided into two groups when it comes to breathing: -those who get their oxygen from the air. Air breathers, creatures with lungs. -those who get their oxygen from water. Water breathers, creatures with gills. And just as lungs can't get oxygen from water, gills can't get oxygen from air.