Which of the following organism has a 2-Chambered heart?

Fishes

The correct answer is Option (4)- Fishes

Fishes have a 2-chambered heart. Unlike mammals, including humans, which typically have a 4-chambered heart, fish hearts generally consist of two chambers: one atrium and one ventricle. This simple heart structure is characteristic of many fish species.

In a 2-chambered heart, blood flows through the heart in a single circuit. Deoxygenated blood is pumped from the heart to the gills, where it picks up oxygen, and then it is distributed to the rest of the body. This is a less efficient system compared to the 4-chambered hearts found in mammals and birds, where oxygenated and deoxygenated blood are kept separate, allowing for more efficient oxygen delivery to the tissues.