!!!!!Ch. 16 study guide COMPLETED!!!!

BIO 188 Study Guide #16 CARDIOVASCULAR PHYSIOLOGY Study Questions **ANS controls HR **Sympathetic increases HR **Parasympathetic decreases HR 1. Trace blood flow in order through the major vessels and circuits. For each vessel or heart chamber, indicate whether the level of oxygenation is relatively high or low. inferior/superior vena cava > right atrium > right AV valve > right ventricle >right SL valve > pulmonary artery > lungs > pulmonary vein > left atrium > left AV valve > left ventricle >left SL valve > aorta *Blue= O2 poor?..*Red=O2 rich 2. What are the phases of the cardiac cycle and what happens during each? Describe the muscular, valve, fluid, and electrical activity associated with each. Systole: ?Lub? sound- ventricles contract, AV valve closes, pressure in the ventricles build up until the aortic and pulmonary valves open. Blood is pumped out of the ventricles and into the aorta or pulmonary artery. Diastole: ?Dup? sound- ventricles relax, pressure in the ventricles falls at the end of systole, aortic and pulmonary valves shut, ventricles fill with blood. 3. Given EDV, ESV, and HR, how do you calculate SV, CO, and EF? What are normal resting values for SV, CO, and EF? On average, how often does an RBC pass through the heart? Normal resting values SV: 70 EDV: 120 ESV: 50 CO: 5.4L EF:0.6 CO= SV x HR SV= EDV-ESV EF= SV/EDV **Any EF below 0.4 is indicative of heart failure RBC passes through the heart every 1 minute. 4. Starting with the outermost, name the three types of ??cardium? and the function of each. Pericardium- great vessels are contained (provides coverage) Myocardium- muscular layer of the heart, aids in contraction Endocardium- lines the internal surface of the heart, assists in forming valves 5. What is the cause of the twisting or torque motion of the heart as it contracts? 6. During one minute, approximately how much time is spent in diastole and how much is spent in systole? 7. Compare and contrast atrial and ventricular contraction in terms of strength, length, timing, valve activity, and maximum blood pressure. 8. How would a massive drop in blood volume affect CO? Why would tachycardia be expected as a result? 9. What factors affect SV? 10. What factors can influence HR? What hormones, if any, regulate these factors? 11. What is the sequence of events in the conducting system (nervous tissue) of the heart through one cardiac cycle? Correlate these events with the signals on an EKG. P: depolarization of the atrial muscle (diastole) Q: depolarization of the ventricular muscles (diastole) R: depolarization of the ventricular muscles (diastole/systole) S: depolarization of the ventricular muscles (systole) T: relaxation and repolarization of the ventricles (diastole) 12. Compare abnormal EKGs with normal EKGs and explain how the diagnoses given in class account for the observed irregularities. Why is rapid conduction of the electrical signal from the Bundle of His to the Purkinje fibers important for efficient pumping of blood? Any difference from the normal PQRST wave is abnormal. The signal is important because it ensures that cardiac action potential spreads rapidly and evenly throughout the ventricular muscle mass. 13. Resistance to blood flow is regulated primarily in which type of vessel? In these vessels, how is blood flow to an organ increased or decreased? 14. Which type of vessel is most elastic and why is this important? Veins because blood tends to accumulate in veins 15. Which type of vessel is least robust (against pressure increase, stresses, etc) and how is its inherent weakness associated with its function? 16. Why does the net fluid flow between the capillaries and interstitial fluid reverse as the blood passes through a capillary bed? If the chemical composition (and hence osmotic pressure) in a capillary bed were constant, would this reversal still occur? 17. How do the mechanisms promoting fluid flow through arteries and veins differ? 18. How do viscosity, vessel length, and vessel diameter affect the total peripheral resistance? Which one of these factors can be most rapidly changed? How does this factor affect CO? 19. What hormones can alter blood pressure? What tissue or organ does each target? What is its effect on that tissue or organ, and how does this change blood pressure? Baroreceptors: Sensitive to BP in aorta and carotid arteries, signals rising BP and inhibits SNS to arteries/arterioles while increasing parasympathetic signaling to the heart?s pacemaker. Results in a slow in HR and dilation if arterioles in peripheral tissues. Chemoreceptors: Located in the medulla, aorta, and carotid arteries. Activated by falls in arterial O2 levels. Renin: Activates angiotensis, released by kidney Angiotensin: Produced when BP to the kidney falls, causes vessels to constrict, causes rise in arterial pressure ADH(vasopressin): Secreted by posterior pituitary, signals a fall in arterial pressure, causes the kidneys to resorb more water and maintain blood volume 20. How do ordinary movements such as walking contribute directly to circulation? Keep blood flow from pooling in lower extremities, promote CV health 21. What is hypertension and how is it defined? High blood pressure, includes 3 separate measurements that are greater than 130/90 22. How might hypertension cause damage to organs such as the brain or tissues such as coronary arteries? High BP can cause 23. What are the cellular components of blood? What are their functions? Their relative abundance within blood? Erythrocytes: Transport O2 and CO2. 5-6 million/microliter Leukocytes: Destroy foreign cells, produce antibodies, roles in allergic response. 5,000-10,000/microliter Platelets: Blood clotting. 250,000-400,000/ microliter 24. What are the major components of plasma? What are their functions? Water: Acts as a solvent. Salts (Na, K, Ca, Mg, Cl, bicarb.): Osmotic balance, pH buffering, regulation of membrane potentials Plasma proteins: Osmotic balance, pH buffering, clotting, immune response. Terms You Should Know afterload aldosterone angiotensin antidiuretic hormone (ADH) aorta aortic valve arteriole artery atrioventricular (AV) node atrioventricular (AV) valve atrium bundle branches capillary cardiac cycle cardiac insufficiency cardiac output cardiac reserve carotid arteries contractility diastole diastolic pressure ejection fraction (EF) elastin end-diastolic volume endocardium endothelium end-systolic volume erythrocytes fibrillation hematocrit hydrostatic pressure hypertension inferior vena cava leukocytes lumen mean arterial pressure (MAP) mitral/bicuspid valve myocardium P wave pericardium plasma platelets preload pulmonary trunk pulmonary veins pulmonic valve pulse pressure Purkinje fibers QRS complex regurgitation semilunar valves sinoatrial (SA) node skeletal muscle pump stroke volume (SV) subclavian arteries superior vena cava systemic circulation systole systolic pressure T wave tachycardia total peripheral resistance (TPR) tricuspid tunica adventitia tunica intima tunica media vasoconstriction vasodilation vasopressin vein venous return (VR) ventricle venule viscosity