The area of a structure in this organ is related to a mean pressure gradient in the Gorlin equation. That structure in this organ bulges, or “balloons,” in Barlow’s syndrome. S3 and S4 are two “gallop” signs used to evaluate this organ’s function. A rare congenital defect of this organ (-5[1])is marked by thickening leading to stenosis, (15[1])as well as this organ’s upper section developing too far to the right. The chordae tendineae regulate the opening and closing of structures in this organ that are affected by the (*) Tetralogy of Fallot. “Regurgitation” (10[1])in this organ is indicated by the splintering of (10[1])R waves in the QRS complex. The conduction of electrical signals by this organ’s AV and SA nodes are measured in an ECG. For 10 points, name this organ whose tricuspid, mitral, and aortic valves regulate the pumping of blood. ■END■