Question

The membrane dividing heart into right and left portions

Answer 1

The left and right ventricles (the main pumping chambers of the lower heart) share a wall of cardiac muscle tissue that separates them, and this is called the ventricular septum. The left and right atria (chambers of the upperheart) are likewise separated by the atrial septum.

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Answer 2

The membrane dividing heart into right and left portions is called atrial septum