ANATOMY

Detailed explanation-1: -A typical heart has two upper and two lower chambers. The upper chambers, the right and left atria, receive incoming blood. The lower chambers, the more muscular right and left ventricles, pump blood out of the heart.

Detailed explanation-2: -The four-chambered heart has a distinct advantage over simpler structures: It allows us to send our “dirty” blood to the cleaners-the lungs-and our “clean” blood to the rest of the body without having to mix the two. That system is very efficient.

Detailed explanation-3: -The heart is made up of four chambers. The upper two chambers are called atria (singular: atrium) and the lower two are known as ventricles (singular: ventricle). Muscular walls, called septa or septum, divide the heart into two sides.

Detailed explanation-4: -The heart of mammals and birds is four-chambered, while fishes have two-chambered hearts and amphibians and reptiles have three-chambered hearts. The hearts of birds and mammals are: Q.