BIOL 1410 Lecture Notes - Superior Vena Cava, Interventricular Septum, Interatrial Septum

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1410
• Professor: Jennifer Mcleese

Document Summary

In cavity called mediastinum (in thoracic cavity between lungs) Coverings = pericardium is double walled sac surrounding heart. 3 layers: fibrous pericardium, outer is dense irregular ct, serous pericardium, 2 parts, parietal pericardium: fused to fibrous pericardium (layers 1 and 2a = pericardial sac, visceral pericardium/epicardium: fused to heart surface (part of heart wall) Inferior and superior vena cava: right atrium. Divides to form 2 pulmonary arteries: left ventricle. Ct fibers around muscle fibers + ct rings between atria and ventricles at the coronary sulcus. Allows openings to remain open at all times (valves open and close) Provide electrical insulation preventing simultaneous contraction of chambers. Chordae tendinaeae: attach cusps to papillary muscles (cardiac muscle), prevents eversion of cusps: semilunar valves: 3 cusps each, aortic: between left ventricle and aorta, pulmonary: between right ventricle and pulmonary trunk. Similarities to skeletal muscle: striated (myofibrils with sarcomeres, has sarcoplasmic reticulum. Intercalated discs: region where 2 fibers meet, contain anchoring and gap junctions.