Heart Review 1. Structure – chambers, type of muscle, sinoatrial node, atrioventricular node, conducting system, intercalated discs, gap junctions. Four chambers of the heart: 1. Right Atrium: Collects blood from systemic circuit 2. Right Ventricle: Pumps blood to pulmonary circuit 3. Left Atrium: Collects blood from the pulmonary circuit 4. Left Ventricle: Pumps blood to systemic circuit
Type of muscle: Consist of 3 tissues layers: 1. Endocardium: “Inner” Is thin, serous membrane of connective tissues and a simple squamous epithelium. 2. Myocardium: “Middle” Thickest layer. Composed of primary of cardiac muscles fibers 3. Epicardium: “Outermost” Similar to “Endocranium” serous membrane of connective tissues Cardiac Muscle Cells - Small size, single central nucleus, branching interconnection between cells, and intercalated discs Sinoatrial Node(SA): “ Pacemaker of the heart” - A small body of specialized muscle tissue in the wall of the right atrium of the heart that acts as a pacemaker by producing a contractile signal at regular intervals - (SA) generates an electrical signal that causes the upper heart chambers (atria) to contract. - Then signal then passes through the (AV) to lower heart chambers (Ventricles), causing them to contract, or pump
Atrioventricular Node (AV): - Connect right atrium to right ventricle and left atrium to left ventricle - Permit blood flow in one direction; atria to ventricles Artery : away from the heart Veins: Towards the heart Conducting System: - Consist of specialized heart muscle cells, and is situated with the myocardium.
- Spring '17