Gills are the respiratory organs found in aquatic animals like fish, amphibians, and some invertebrates. Their function is gas exchange, specifically:

* Taking in oxygen from the water.

* Releasing carbon dioxide (a waste product of respiration) into the water.

How do gills work?

Gills are made up of thin, folded tissues with a large surface area. This allows for efficient diffusion of gases. Water flows over the gills, and oxygen dissolved in the water diffuses across the gill membranes into the blood. At the same time, carbon dioxide from the blood diffuses into the water.

Let me know if you want to learn more about the specific types of gills in different animals!