* Gills: Fish breathe using gills, which are feathery structures located on either side of their head. The gills are filled with tiny blood vessels called capillaries.
* Water Flow: Water constantly flows over the gills, bringing oxygen to the blood and carrying away carbon dioxide.
* Diffusion: Oxygen from the water diffuses across the thin membranes of the gills into the bloodstream. At the same time, carbon dioxide from the blood diffuses into the water.
* No Water Loss: This exchange of gases happens through a process called diffusion. There's no significant water loss during this process.
So, fish don't lose water when they breathe. Instead, they use the water to obtain the oxygen they need for survival.