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Ch. 20Heart
cardiovascular system, the heart
Question | Answer |
---|---|
cavity housing the heart | mediastinum |
On what side of the body is the heart located? | 2/3 on Left |
Coverings of the heart. | Pericardium:1)Fibrous pericardium(dense, irregular, nonelastic connective tissue) 2)Serous pericardium (parietal layer + visceral layer) |
Inflammation of the pericardium .Cause, bad? | Pericardisis. Usually caused by virus. Very painful. Serious. |
Layers of heart wall. | Epicardium (smooth + thin), myocardium (muscle), endocardium (smooth, lines heart chambers). |
Pouches that sit ontop of atriums. Function? | Auricles. Increase blood volume for the heart. |
Groove btw. atria and ventricles. Contains what. | Deep coronary sulcus. Contains fat and blood vessels. |
Splits left and right ventricles. | Anterior and posterior interventricular sulcus. |
Blood vessel away from the heart. | Artery |
Blood vessel toward the heart. | Vein. |
Largest vein bringing blood to the heart. | Superior and inferior vena cava. |
Fetal passageway from aorta to pulmonary artery. Point? Disappears when? | Ductus arteriosis bipasses the lungs in the fetus. 2-3 months. |
Blood comes to the right atrium from where? | Vena cavas and coronary sinus |
Muscles of the inside walls of the atria. | Pectinate |
Muscles of the walls of the ventricles. | Trabeculae Carneae |
Tendons between valves and walls of ventricles (names these attachments). | chordae tendinae attach to papillary muscle. |
Remnants of fetal tube in heart. | Ligamentum Anteriosum |
Hole between left and right atrium. | Fossa ovalis. |
Biggest and thickest cavity in heart. | Left ventricle. |
Artery networks that can grow with exercise. | Anastomoses. |
"widow maker" | LAD= left anterior descending artery feeds mainly the left side of the heart. |
Pouch where blood from heart gets deposited. | Coronary sinus. |
How many nuclei in a cardiac muscle cell. | 1 to 2 |
What connects two cardiac muscle cells? Function? | Intercalated discs = desmosomes (cementing nodules) + gap junctions (openings) for communication of nerve impulses. |
Stages/path of the cardiac action potential/nerve transmission. | 1)SA (sinoatrial) node/ "pacemaker"in right atrium. 2) reaches AV (atrioventricular) node. 3) reaches Bundle of His (nerve portion) and splits in two at Purkinje Fibers at the base of ventricles. Carries impulse around to SA. |
Difference between skeletal muscle and cardiac muscle action potential chains. | Refractory period longer w/cardiac muscle because of wait for ventricles to fill with blood. |
ECG? Waves on ECG. | Electrocardiogram. P wave (atrial depolarization/contraction), QRS complex (ventricular depolarization/contraction), T wave (ventricular repolarization). |
What does BP mean? | Systole (ventricles in contraction) over Diastole (ventricles relaxed) |
Listening to anything. | Auscultation |
Sounds of heart. | S1= lubb= louder and stronger, closrue of AV valves. S2 = dubb= softer and weaker, closer of SL valves. |
SL valves | Semi-lunar valves = pulmonic and aortic valves. |
What is a murmer. | A schlhhh after lubb dubb is some blood going back through valves that haven't completely closed. |
Know places to best listen to valves. | know them |
Amount of blood ejected from left and right ventricle. | Cardiac output = stroke volume x HR |
How much blood does the heart pump in 1 minute. | 5 liters |
3 things that maintain stroke volume between each ventricle. | Prelode (stretch), contractility (amount of Calcium), and afterload (pressure needed for ejection out of SL valves). |
Increase and decrease contractility of ventricles. | Calcium channel blockers and parasympathetic decrease. More calcium, sypathetic, epinephrine and norepinephrine increase contractility. |
What part of the brain regulates heart rate? | Medulla oblongata. |
What three receptors influence heart rate? | Proprioceptors (positively), chemoreceptors (less o2, greater HR), baroreceptors (negatively). |
Where do the sympathetic and parasympathetic nerves come from that innervate the heart? | Sympathetic from thoracic region and use norepinephrine. Parasympathetic from vagus CN X and use Ach. |
How do certain cations regulate the heart? | More K or NA in the blood lowers HR and contractility. |
Fast HR. Slow HR. Normal HR. | Tachycardia. Bradycardia. 60-80/90. |
Enlarged heart. | Hypertrophy. |