Birds have a what chambered heart?

Birds have a four-chambered heart. This means that their hearts are divided into four separate chambers: two atria (singular: atrium) and two ventricles. The atria are the upper chambers of the heart and the ventricles are the lower chambers. The right atrium receives blood from the body and the left atrium receives blood from the lungs. The right ventricle pumps blood to the lungs and the left ventricle pumps blood to the body.