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Anatomy (Heart)
Chapter 12
| Question | Answer |
|---|---|
| Pulmonary Circuit | carries blood to and from the exchange surfaces of the lungs |
| Systemic Circuit | transports blood to and from the rest of the body |
| Arteries | efferent vessels,carry blood away from the heart |
| Veins | afferent vessels, return blood to the heart |
| Capillaries | small thin walled vessels between the smallest arteries and the smallest veins; the thin walls permit the exchange of nutrients,dissolved gases, and waste products between the blood and surrounding tissues |
| Right Atrium | receives blood from the systemic circuit |
| Right Ventricle | discharges blood into the pulmonary circuit |
| Left Atrium | collects blood from the pulmonary circuit |
| Left Ventricle | ejects the blood into the systemic circuit |
| Mediastinum | connective tissue mass that divides the thoracic cavity into 2 plueral cavities;also contains the thymus,esophagus,and trachea |
| Pericardial Cavity | this cavity surrounds the heart |
| Pericardium | serous membrane lining the pericardial cavity |
| Base | top half of the heart |
| Visceral Pericardium | epicardium; covers the outer surface of the heart |
| Parietal Pericardium | lines the inner surface of the pericardial sac which surrounds the heart |
| Pericardial Fluid | acts as a lubricant,reducing friction between the opposing surfaces as the heart beats |
| Auricle | lumpy wrinkled flap as part of the atria |
| Coronary Sulcus | deep groove usally filled with substantial amounts of fat, marks the border between the atria and the ventricles |
| Anterior/Posterior Interventricular Sulcus | marks the border between the left and right ventricles |
| Apex | inferior,pointed tip of the heart |
| Epicardium | covers the outer surface if the heart |
| Myocardium | muscular wall of the heart, contains cardiac muscke tissue, blood vessels and nerves |
| Endocardium | inner surface of the heart;simple squamous epithelium that is continuous with the endothelium of the attatched vessels |
| Intercalated Discs | interlocking membranes of adjacent cells are held together bt desmosomes and linked by gap junctions |
| Superior Vena Cava | delivers lood from the head, neck, upper limbs, and chest |
| Inferior Vena Cava | carries blood from the rest of teh trunk, the viscera,and the lower limbs |
| Coronary Sinus | opening into the right atrium slightly below the connection with the inferior vena cava |
| Fossa Ovalis | allows blood to flow from the right atrium to the left atriumwhile the lungs were developing at birth; closes and after 48 hrs is permanently sealed |
| Right Atrioventricular Valve (AV) | Tricuspid Valve |
| Chordae Tendineae | connective tissue fibers bracing each cusp |
| Papillary Muscles | cone shaped projections on the inner surface of the ventricle; contraction of these muscles tenses the chordae tendineae limiting the movement of the cusps and preventing the backflow of blood into the right atrium |
| Pulmonary Trunk | blood leaving right ventricle flows here; start of pulomonary circuit |
| Pulmonary Semilunar Valve | guards entrance to pulmonary trunk |
| Left/Right Pulmonary Arteries | branch repeatedly into the lungs |
| Left/Right Pulmonary Veins | oxygenated blood moes into here; delivered into left atrium |
| Left Atrioventricular Valve | bicuspid valve; mitral valve |
| Aortic Semilunar Valve | blood leaving left ventricle passes through here before moving into the aorta (start of systemic system) |
| Atrioventricular valves | prevent backflow from venticles into atria |
| Regurgitation | backflow of blood into the atrium; heart murmur |
| Aortic Sinuses | prevent the cusps from sticking to the wall of the aorta when the valve opens |
| Fibrous Skeleton | dense bands of elastic connective tissue that encircle the bases of the large blood vessels carrying blood away from the heart and each of the heart valves |
| Coronary Circulation | supplies blood to the muscle tissue of the heart |
| Coronary Arteries | originate at the base if the aorta |
| RCA | provides blood to the right atrium and portions of both ventricles |
| LCA | supplies blood to the left ventricle left atrium and interventricular septum |
| Anastomoses | small tributaries from branches of the left and right coronary arteries |
| Great/Middle Cardiac veins | carry blood away from the coronary capillaries |
| Coronary Sinuses | large thin walled vein in the posterior portion of the coronary sulcus |
| Infarct | area of dead tissue caused by an interruption in the blood flow |
| Myocardial Infarction | heart attack,coronary circulation becomes blocked and cardiac muscle cells die from the lack of oxygen |
| Heartbeat | entire heart,atria and ventricles contracts in a coordinated manner so that blood in flows in the correct direction at the proper time |
| Contractile Cells | produce powerful contractions that propel blood;bulk of the hearts muscle tissue |
| Depolarization-Repolarization Process | 250-300 msec,25-30 times as long as an action potential in a skeletal muscle fiber |
| Conducting System | network of specialized cardiac muscle cells that initiates and distributes electrical impulses |
| Nodal Cells | responsible for establishing the rate of cardiac contraction and are located at the sinoatrial (SA) and (AV) Nodes |
| Conducting Cells | distribute the contractile stimulus to the general myocardium |
| Major Sites of conducting cells | AV Bundle, bundle branches, and Purkinje fibers |
| Pacemaker cells | nodal cells that reach threshold first |
| Sinoatrial Node (SA node) | cardiac pacemaker,tissue embedded int he posterior wall of the right atrium near the entrance of the superior vena cava |
| Atrioventricular Node (AV Node) | generate 40-60 action potential per minute |
| AV Bundle | bundle of his |
| Left/Right Bundle Branches | radiate across the inner surface of the left and right ventricles |
| Purkinje Fibers | convey the impulses to the contactile cells of the venticular myocardium |
| Bradycardia | slow heart beat (less than 60 bpm) |
| Tachycardia | fast heart beat (more than 100 bpm) |
| EKG or ECC | recording of heart beat |
| P wave | atria begin contracting;accompanies the depolarization of the atria |
| QRS Complex | strong signal |
| T wave | ventricular repolarization |
| Cardiac Arrhythmias | abnormal patterns of cardiac activity |
| Cardiac Cycle | period between the start of one heart beat and the start of the next |
| systole | contraction |
| Diastole | relaxation-filling of blood |
| "Lubb" | AV Valves closes and semilunar opens |
| "Dubb" | semilunar valve close |
| Stroke Volume (SV) | amount ejected by a ventricle during a single heart beat |
| Cardiac Output (CO) | amount of blood pumped by each ventricle in 1 min |
| CO | = SV x HR (heart rate) |
| Atrial reflex | produces adjustments in heart rate to an increase in the venous return |
| Venous return | flow of venous blood to heart |
| Filling time | duration of ventricular diastole when blood can flow into the ventricles |
| Frank-Starling Principle | "more in = more out" |
| Cardioacceleratory Center | activates the smpathetic motor neurons |
| Cadioinhibitory Center | controls the parasympathetic motor neurons |