Where the gills on perch fish?

Here's a breakdown:

* Gills: These are feathery, thin structures filled with blood vessels that extract oxygen from the water and release carbon dioxide.

* Operculum: This is a bony flap that covers and protects the gills. It also helps the fish pump water over the gills for respiration.

You can see the operculum moving as the perch breathes, and if you're lucky enough to catch one, you might even see the gills themselves if you gently lift the operculum.