How many chambers does a fish heart have?

A fish heart has two chambers, consisting of one atrium and one ventricle. This anatomical structure is efficient for the circulatory needs of fish, allowing blood to flow in a single circuit. In fish, oxygen-depleted blood from the body enters the atrium, is pumped into the ventricle, and then sent to the gills for oxygenation. After the blood is oxygenated in the gills, it circulates to the rest of the body.

While other vertebrates possess more complex heart structures, fish have adapted to their aquatic environment with this simpler arrangement, which effectively supports their physiology. Understanding this basic anatomical characteristic is crucial for veterinary professionals working with aquatic species, as it underlines the differences in cardiovascular function across various animal groups.