What is the difference between a human respiration and a fish respiration?

The humans or mammals take in oxygen which is present in the surrounding air to breathe. This oxygen is traveled to the lungs from the nose through the windpipe. Close to the lungs, windpipe is splitted into two tube known as bronchi. Then the bronchi splitted into many branches also known as bronchioles. After the oxygen pass bronchioles it goes straight to the alvioles or the air sacs.

In the case of fishes, the oxygen is absorbed by the water and the fishes take in the water through their mouth. Near their mouth their is a small bloo vessel which is able to absorb oxygen. This oxygen then travels to different parts of their body and water is removed from their gills which is near the opening of their mouth. Gill is also protect by a cover called gill cover to protect any water from entering through the gills.