The heart is located... |
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in the mediastinum of the thoracic cavity.
(between the sternum, lungs and thoracic vertebrae) |
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The serous membrane of the heart is... |
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the pericardium.
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Outer Parietal |
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attaches heart to mediastinum. has fibrous tissue so heart doesn't over expand. |
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Visceral Layer |
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called epicardium. lines the surface of the heart. |
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Pericardial Cavity |
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space between parietal and visceral layer. filled with fluid to reduce friction. Both layers have mesothelium that secrete serous fluid. |
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Myocardium |
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muscle of the heart. uninucleated cardiac muscle cells. |
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Endocardium |
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line the heart chambers. inner layer of the heart. endothelial cells. |
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auto-rhythmic |
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regulates its own relaxation and contraction phases without nerve stimulation. can be affected by nerve stimulation. |
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Sinu-Atrial Node (SA Node) |
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action potential originates here. |
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atrivoventricular node (AV node) |
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pass slowly through atrium wall so atria can contract. |
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atrioventricular bundle |
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signal passes through here to divide into left and right bundles to the ventricles. |
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purkinje fibers |
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begin at apex of ventricles. stimulate ventricle walls simultaneously to elicit stronger contraction. |
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Baroreceptors |
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located in the carotid sinus and aortic arch respond to increase in blood pressure. this stretches the carotid arteries and aorta. increase action potential generation. |
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Medulla Oblongatta |
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receives information from the vagus and glossopharyngeal nerves from the heart to increase parasympathetic stimulation. |
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Superior and Inferior Vena Cava |
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deliver blood to right atrium. |
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tricuspid (AV) valve |
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connects right atrium and ventricle |
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pulmonary semilunar valve |
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empties blood into the pulmonary arteries. |
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bicuspid AV Valve |
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empties blood from left atrium into the left ventricle |
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systemic semilunar valve |
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empties blood from left ventricle to the aorta. |
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coronary sinus |
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all coronary veins merge here located in coronary sulcus empties deoxygenated blood to right atrium |
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coronary veins |
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great c.v., small c.v., middle c.v., posterior c.v. |
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chordae tendineae |
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hold valves shut |
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