What is the function of the septum in the heart?

• A. Forms the heart valves
• B. Anchors the heart to the diaphragm
• C. Conducts impulses through the ventricles
• D. Separates the left and right sides of the heart

Answer: (D)

The septum’s job is to separate the heart into left and right sides, keeping oxygen-rich blood on the left and oxygen-poor blood on the right. It consists of the interatrial septum between the atria and the interventricular septum between the ventricles, ensuring the two circuits (systemic and pulmonary) stay distinct so the heart pumps efficiently. The other options describe different structures: valves are formed by leaflets and supporting tissue, not the septum; the diaphragm attachment involves pericardial and diaphragmatic structures rather than a septal wall; and impulse conduction is handled by the cardiac conduction system (like the bundle branches and Purkinje fibers), not the septum.