Many people are familiar with fish, but are unsure of the important organs and anatomy exclusive to the fish that helps it survive in its aquatic environment. The fish is highly evolved and its body regulates many important functions on a daily basis.
There are many varieties of fin shapes and sizes. The most well known is the ray fin, which is fan-like in structure. Fins propel fish through their aquatic environments.
Gills allow fish to breathe. Fish take oxygen-filled bubbles in through their mouths. The gills are full of carbon dioxide bubble-rich blood. Since the gills are so thin, the oxygen passes into the gills, displacing the carbon dioxide bubbles and supplying the fish with fresh oxygen.
The operculum is a boney flap that covers and protects the gills from damage. It forms most of the side of the head behind the eye. The back edge of the operculum defines the area between the head and body in most fish.
The swim bladder is located in the body cavity. It contains gas, usually oxygen, which helps the fish keep its buoyancy. It allows the fish to maintain its depth in water without floating upward or sinking.
Fish anatomy and its intricacies are no accident. Years of evolution have led to highly evolved organs and mechanisms. The fish is host to many important developments and mechanisms that allow it to breathe, live and exist under water.