NU 606 EXAM 3 ACTUAL EXAM QUESTIONS WITH COMPLETE SOLUTION GUIDE (A+ GRADED 100% VERIFIED) LATEST VERSION 2025/2026

NU 606 EXAM 3 ACTUAL EXAM QUESTIONS WITH COMPLETE SOLUTION GUIDE (A+ GRADED 100% VERIFIED) LATEST VERSION 2025/2026 what are the two layers of the pericardial sac Correct Answer outer fibrous pericardium anchors the heart to diaphragm visceral pericardium (epicardium) has a serous membrane what is unique about cardiac muscle (myocardial fibers) Correct Answer - no nerves are present intercalated discs at the junctions between fibers (they contain desmosomes, connections to prevent muscle cells from separating during contraction, and gap junctions, which permit ions to pass from cell to cell which facilitates rapid transmission of impulses what ensures that all muscle fibers of the two atria followed by the two ventricles contract together or shortly after as it were Correct Answer gap junctions and desmosomes 1 where does a conduction impulse start Correct Answer all muscle cells can start it, but it usually originates in the sinoatrial node - the pacemaker what can alter the SA node impulses Correct Answer autonomic nervous system fibers and circulating hormones such as epinephrine what is the only anatomical connection between atrial and ventricle conduction in the heart Correct Answer AV node where does the cardiac electrical impulse go after the AV node Correct Answer av bundle/ bundle of His, the right and left bundle branches, and the terminal purkinje network of fibers what stimulates ventricular contraction 2 Correct Answer terminal purkinje fibers? what does the P wave represent in an ECG Correct Answer atrial depolarization what does the QRS wave represent in an ECG Correct Answer depolarization of the ventricles - during that time it masks the effect of atrial repolarziation what does the T wave represent on an ECG Correct Answer ventricular repolarization where is the cardiac control center and what does it do Correct Answer medulla of the brain. responds to changes from the baroreceptors (which detect BP and are located in the aorta and carotid) . activate sympathetic nervous system or parasympathetic nervous system to alter the rate and force of cardiac contractions 3 What does activation of the sympathetic nervous system (SNS) do? Correct Answer tachycardia and contractility What does activation of the parasympathetic nervous system do? Correct Answer bradycardia through Vegas nerve How do beta blockers work? Correct Answer block normal SNS activation in an otherwise damaged heart, so that it does not need to increase force or rate after the heart has been damaged. What are sulcus (sulci)? Correct Answer shallow grooves where the vessels of the coronary arteries lie when is blood flow greater through the myocardium Correct Answer diastole (relaxation) 4 how does routine aerobic physical exercise help coronary circulation Correct Answer development of collateral circulation what does a blockage of the right coronary artery impact? Correct Answer AV node (resulting in dysrhythmias), supplies right side of the heart and inferior portion of the left ventricle as well as posterior interventriucular septum. what does blockage of the left coronary artery impair? Correct Answer pumping capability of the left ventricle - congestive heart failure- brings blood to anterior wall of ventricles, anterior septum, and bundle branches cardiac cycle step 1 Correct Answer atria relaxed and filling - the pulmonary veins filling the left atrium, the inferior and superior venue cave fill the right atrium 5 cardiac cycle step 2 Correct Answer the av valves open as the pressure of the blood in the atria increases and ventricles are relaxed cardiac cycle step 3 Correct Answer blood flows into ventricles - almost emptying atria cardiac cycle step 4 Correct Answer conduction system stimulates the atrial muscle to contract, forcing any remaining blood into the ventricles cardiac cycle step 5 Correct Answer the atria relax cardiac cycle step 6 Correct Answer the two ventricles begin to contract, and pressure increases in the ventricles 6 cardiac cycle step 7 Correct Answer the av valves close cardiac cycle step 8 Correct Answer all valves are closed, and the ventricular myocardium continues to contract which builds pressure cardiac cycle step 9 Correct Answer increase pressure opens the semilunar valves, blood is forced into the pulmonary artery and aorta. right ventricle doesn't need as much pressure because the pulmonary circulation is not as high pressure and systemic circulation. cardiac cycle step 10 Correct Answer atria have begun to fill, ventricles relax, the aortic and pulmonary valves close to prevent back flow. what causes cardiac heart sounds 7 Correct Answer valves closing - lubb is AV valves at systole, and dubbings is semilunar valves closing with diastole why is there a pause after AV node conduction Correct Answer allow ventricular filling what impacts stroke volume Correct Answer sympathetic stimulation and venous return Cardiac reserve is: Correct Answer the ability of the heart to increase cardiac output when needed Preload Correct Answer volume of blood in ventricles at end of diastole - ventricles are at their maximum volume Afterload 8 Correct Answer The force or resistance against which the heart pumps to eject blood from the ventricles, deterred by peripheral resistance to the opening of semilunar valves - for example impacted by high diastolic pressure :) what does the circumflex artery nourish? Correct Answer left atrium and the lateral and posterior walls of the left ventricle systolic pressure is: Correct Answer highest pressure, pressure exerted by the blood when ejected from the left ventricle diastolic pressure Correct Answer lower pressure, pressure that is sustained when the ventricles are relaxed what impacts blood pressure