THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -The interatrial septum is a thin wall of tissue that separates the two upper chambers of the heart, called the right and left atria.

Detailed explanation-2: -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 right and left ventricles-pump blood out of your heart.

Detailed explanation-3: -cardiovascular system …a partition known as the interatrial septum; the lower chambers, the ventricles, are separated by the interventricular septum. The atria receive blood from various parts of the body and pass it into the ventricles.

Detailed explanation-4: -The upper chambers are called the left and right atria and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles. These are referred to as the atrial and ventricular septum.