EVERYDAY SCIENCE

Detailed explanation-1: -But instead of lungs, they use gills. Gills are branching organs located on the side of fish heads that have many, many small blood vessels called capillaries. As the fish opens its mouth, water runs over the gills, and blood in the capillaries picks up oxygen that’s dissolved in the water.

Detailed explanation-2: -Fish take water into their mouth, passing the gills just behind its head on each side. Dissolved oxygen is absorbed from-and carbon dioxide released to-the water, which is then dispelled. The gills are fairly large, with thousands of small blood vessels, which maximizes the amount of oxygen extracted.

Detailed explanation-3: -Gills are the organs for respiration in fishes. Gills are capable of absorbing oxygen from the water flowing over their surface. Was this answer helpful?

Detailed explanation-4: -Gills help fish breathe because it makes oxygen so they can breathe and it makes air for them. The gills help the fish breathe because if they did not have gills, the fish would not breathe.

Detailed explanation-5: -Gills are projections present on the skin of an organism which lives underwater. It is richly supplied with blood vessels which help in the exchange of gasses. Such organisms are called amphibians.