Solved by a verified expert:1) The primary pacemaker of the heart is:the atrioventricular (AV) node.the bundle of His.the sinoatrial (SA) node.Bachmann’s bundle.2) The coronary arteries originate in the:right atrium.pulmonary artery.coronary ostia of the aorta.superior vena cava.3) Which statement describes depolarization?When cardiac cells are unable to contractWhen ions cross cell membranes to cause the cell to contractWhen cardiac cells are returning to their resting stateWhen cardiac cells are fully at rest4) The area of the heart just above the diaphragm is called the:inferior wall.base.posterior wall.anterior wall.5) Identifying the location and etiology of cardiac abnormalities:can never be done if only the electrocardiograph (ECG) is used.is critical to determine the appropriate treatment and predict possible complications.can always be done using only the ECG.isn’t necessary to make appropriate treatment decisions.6) Which are the two phases of the cardiac cycle?Diastole and systoleImpulse transmission and resting potentialDepolarization and repolarizationAutomaticity and conductivity7) Which statement best describes cardiac cells at rest?Cardiac cells at rest are considered polarized, meaning that no electrical activity takes place.Cardiac cells at rest have positive electrical charges in the cell and negative charges outside.Cardiac cells at rest exhibit an action potential which is when the transmission of electrical impulses take place.Cardiac cells at rest are electrically charged in preparation for contraction.8) Cardiac cells have the ability to generate an electrical impulse which is called:automaticity.conductivity.contractility.vasodilation.9) The coronary artery that supplies the anterior and ventricular septal walls of the heart is the:left anterior descending artery.posterior descending artery.right coronary artery.left circumflex artery.10) Which cardiac layer is the thick muscular layer?PericardiumMyocardiumEpicardiumEndocardium