Ch20 Homework - The Heart - 35 mins PDF

4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Ch20 - Homework - the Heart ~35 mins Due: 11:59pm on Tuesday, April 9, 2024 To understand how points are awarded, read the Grading Policy for this assignment. PhysioEx Exercise 5 > Activity 5: Overview and Pre-lab Quiz for Studying the Effect of...

4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Ch20 - Homework - the Heart ~35 mins Due: 11:59pm on Tuesday, April 9, 2024 To understand how points are awarded, read the Grading Policy for this assignment. PhysioEx Exercise 5 > Activity 5: Overview and Pre-lab Quiz for Studying the Effect of Blood Vessel Radius on Pump Activity Read the introduction and then answer the Pre-lab Quiz questions to the right. Exercise 5 > Activity 5: Studying the Effect of Blood Vessel Radius on Pump Activity Part A During the ejection period, _______. ANSWER: blood is pumped into the aorta blood is pumped into the aorta and the pulmonary trunk the atria are filling blood is pumped into the pulmonary trunk the ventricles are filling Correct Part B Cardiac output is _______. ANSWER: equal to heart rate multiplied by stroke volume. equal to heart rate plus stroke volume. equal to heart rate divided by stroke volume. Correct Part C https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 1/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins The left side of the heart pumps blood _______. ANSWER: through the aortic valve through the tricuspid valve and to the lungs to the lungs through the tricuspid valve Correct Part D What variable(s) can the cardiovascular system alter to maintain blood pressure? ANSWER: heart rate, stroke volume and resistance stroke volume resistance heart rate Correct Chapter Test - Chapter 20 Question 3 Part A Blood returning to the heart from the pulmonary circuit first enters the __________. ANSWER: left atrium pulmonary valve right atrium pulmonary trunk Correct Chapter 20 Reading Quiz Question 7 Part A Susan visits the doctor for a stress test before beginning a workout schedule. On the treadmill at a full run for 5 minutes, her heart rate was 150 bpm and her stroke volume was determined to be 120 mL. What is her calculated Cardiac Output? ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 2/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins 18 L / min 20 L / min 15 L / min It is the same as her SV. Correct Chapter 20 Reading Quiz Question 9 Part A The amount of blood pumped by the left ventricle in one minute during the cardiac cycle is called the __________. ANSWER: ejection fraction end-systolic volume stroke volume cardiac output Correct Art-based Question: The Heart Question 3 Part A Which of the labeled valves will open during ventricular systole to allow the flow of blood to the lungs? https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 3/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins ANSWER: the atrioventricular valve labeled A the semilunar valve labeled B the semilunar valve labeled C the atrioventricular valve labeled D Correct Art-based Question: The Heart Question 4 Part A Into which chamber of the heart will blood flow next after the vessel indicated by the red arrow? ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 4/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins right ventricle right atrium left ventricle left atrium Correct Chapter Test - Chapter 20 Question 19 Part A If you know both the heart rate and stroke volume, you can calculate the __________. ANSWER: end-diastolic volume cardiac output ejection fraction end-systolic volume Correct Chapter 20 Reading Quiz Question 4 Part A On an ECG, what phase of the cardiac cycle is masked by the QRS complex? ANSWER: atrial repolarization ventricular repolarization ventricular depolarization atrial depolarization Correct Chapter Test - Chapter 20 Question 12 Part A The first heart sound, "lubb," is caused by the ________. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 5/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins ANSWER: closing of the semilunar valves regurgitation of the atrioventricular valves closing of the atrioventricular valves blood flowing into the ventricles Correct Chapter 20 Reading Quiz Question 3 Part A During the plateau phase of the cardiac action potential, which ion is entering the cardiac muscle cell? ANSWER: oxygen sodium potassium calcium Correct Chapter Test - Chapter 20 Question 6 Part A The pulmonary veins carry __________ blood to the __________ atrium. ANSWER: deoxygenated; left oxygenated; right deoxygenated; right oxygenated; left Correct Chapter Test - Chapter 20 Question 16 Part A https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 6/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Which of these statements concerning the cardiac cycle is FALSE? ANSWER: Ventricular systole begins at the peak of atrial systole. Aortic pressure is greater than pulmonary trunk pressure. Cardiac cycle begins with atrial systole. AV valves close before semilunar valves open. Correct Chapter 20 MC In-Text Figure Based Question 1 Part A The ________ side of the heart supplies blood to the systemic circuit, while the ________ side of the heart supplies blood to the pulmonary circuit. (Figure 20-1) ANSWER: left; right superior; inferior right; left inferior; superior left; superior Correct Chapter Test - Chapter 20 Question 5 Part A The __________ valve prevents backward flow of blood into the left ventricle. ANSWER: bicuspid tricuspid pulmonary aortic Correct Chapter Test - Chapter 20 Question 7 https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 7/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Part A Which of the following statements is true about the SA (sinoatrial) node? ANSWER: The action potential created by the pacemaker cells of the SA node directly stimulates the contractile cells of both the atria and ventricles. The pacemaker cells, which establish the heart rate, are located only in the SA node. Pacemaker cells in the SA node form a pathway between the SA and AV nodes. The rate of spontaneous depolarization of nodal cells is the fastest in the SA node. Correct Chapter 20 Clinical Note Question 1: Faulty Heart Valves Faulty Heart Valves Each of the four heart valves must open and close crisply and precisely to permit the proper flow of blood through the heart. The most common valve to falter is the mitral valve. One scenario responsible for mitral malfunction is an untreated bacterial or viral infection that infiltrates the valve cusps. The cusps become inflamed and later scar, resulting in a faulty valve. A valve can malfunction in one of three ways: (1) It can become rigid (a stenotic valve) so that it does not open fully, (2) it can fail to close properly (a regurgitant valve), or (3) it can actually flop backwards (a prolapsed valve). Faulty valves are heard as heart murmurs with a stethoscope. Part A Sam has been diagnosed with having pulmonary edema. Which heart valve is most likely malfunctioning and not closing properly? ANSWER: mitral valve aortic semilunar valve pulmonary semilunar valve tricuspid valve Correct IP: Arterial Baroreceptor Reflex Click on the link or the image below to view an animation on arterial baroreceptor reflex from Interactive Physiology (IP), then answer the questions to the right. IP: Arterial Baroreceptor Reflex https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 8/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Part A Where are the sensors for the arterial baroreceptor reflex located? Hint 1. The arterial baroreceptor reflex is a typical negative feedback system with sensors, a control center, and effectors. ANSWER: cardiovascular centers in the medulla oblongata The sympathetic and parasympathetic nervous systems carotid sinus and aortic arch Correct Yes, the sensors are the arterial baroreceptors themselves, located at the carotid sinus and aortic arch. They detect changes in blood pressure by the degree of stretch on the blood vessel. Part B If blood pressure is increased at the arterial baroreceptors, what would happen with the activity level of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS)? Hint 1. Think about how each system would affect blood pressure. ANSWER: increased PNS and SNS activity decreased PNS activity and increased SNS activity increased PNS activity and decreased SNS activity Correct Yes, the PNS activity would increase and the SNS activity would decrease in an attempt to lower blood pressure. Part C Which of the following would cause vasodilation of arterioles? Hint 1. Vasodilation would result in a decrease in blood pressure. ANSWER: decreased activity of the parasympathetic nervous system increased activity of the parasympathetic nervous system decreased activity of the sympathetic nervous system increased activity of the sympathetic nervous system Correct Yes, a decrease in the activity of the sympathetic nervous system would result in decreased activity of vasomotor fibers, resulting in vasodilation. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 9/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Part D Stimulation of the adrenal medulla would result in which of the following? Hint 1. The adrenal medulla is part of which system in the autonomic nervous system? ANSWER: a decrease in cardiac output a decrease in blood pressure vasodilation of arteries an increase in heart rate and contractility Correct Yes, epinephrine and norepinephrine are released from the adrenal medulla and act as part of the sympathetic nervous system, increasing heart rate and contractility. Epinephrine and norepinephrine have other effects that would also increase blood pressure. Part E A decrease in blood pressure at the arterial baroreceptors would result in which of the following? Hint 1. Think about how the sympathetic and parasympathetic nervous systems would alter blood pressure. ANSWER: vasodilation of arterioles a decrease in heart rate an increase in heart contractility a decrease in cardiac output Correct Yes, sympathetic nervous system activity would be increased because of the low blood pressure. Sympathetic fibers go to the ventricles of the heart and increase their contractility. An increase in contractility would increase stroke volume which would lead to an increase in cardiac output and blood pressure. Chapter Test - Chapter 20 Question 14 Part A What happens during isovolumetric contraction? ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 10/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Blood stops flowing into the atria. All heart valves are closed, and the ventricular myocardium is relaxing. Semilunar valves open, and ventricles eject blood into the pulmonary and aortic trunks. Ventricular pressure rises. Correct Chapter 20 Reading Quiz Question 10 Part A How is heart rate controlled? ANSWER: Heart rate is controlled through the cardiac plexus. Parasympathetic and sympathetic divisions of the ANS control heart rate. Dual innervation controls the heart rate. All the listed answers are correct. Correct Chapter Test - Chapter 20 Question 13 Part A During ventricular systole, the blood pressure __________ and ventricular volume __________. ANSWER: decreases; decreases decreases; increases increases; decreases increases; increases Correct Chapter Test - Chapter 20 Question 9 Part A An action potential in cardiac contractile cells is the same as an action potential in skeletal muscle cells EXCEPT for ______. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 11/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins ANSWER: the movement of potassium ions out of the cell during repolarization as the membrane potential approaches +30mV, the voltage-gated sodium channels close, and sodium begins to be actively transported out of the cell at threshold, voltage-gated sodium channels open, and there is a massive influx of sodium ions the presence of a plateau phase in cardiac contractile cells Correct SmartArt Video: Cardiac Cycle Watch the SmartArt Video for chapter 18, and then complete the question at right. Part A Which of the following statements is correct concerning the cardiac cycle? ANSWER: The event of the cardiac cycle that completes ventricular filling is ventricular systole. The first event of ventricular systole is ventricular ejection. In late ventricular diastole, all chambers are relaxed and filling to about seventy percent of their capacity. The backflow of blood towards the ventricles causes the semilunar valves to open. At the beginning of the cardiac cycle, the atria are relaxed and the ventricles are contracting. Correct The completion of the cardiac cycle occurs when all the chambers of the heart are relaxed which occurs during late ventricular diastole. Spotlight Figure 20.13: Cardiac Arrhythmias https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 12/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Read through the Chapter 20 Spotlight Activity, Cardiac Arrhythmias, and answer the following questions. Part A - Premature Contractions Premature contractions are common and typically not dangerous. If the premature contractions are due to aberrant Purkinje fibers, you can conclude all of the following are taking place EXCEPT __________. Select the best answer. Hint 1. Where Are Purkinje Fibers Located? Purkinje fibers are located in the ventricular endocardium. ANSWER: atrial premature contractions occurring epinephrine exacerbating the premature contractions Purkinje fibers acting as an ectopic pacemaker stimulatory drugs increasing the frequency of premature contractions Correct Depolarizing Purkinje fibers or ventricular myocardial cells that reach threshold before the SA node trigger premature ventricular contractions (PVCs). Epinephrine, some stimulatory drugs, and some ions can increase the number of PVCs. Part B - Abnormal Patterns of Cardiac Electric Activity Several distinct abnormalities of cardiac electric activity characterize cardiac arrhythmias. Which of the following is NOT one of these abnormalities? Select the best answer. Hint 1. Know Your Definitions Knowing the definitions of the keywords in the answer choices will quickly illuminate the correct choice. For instance, ectopic literally translates to “out of place,” and fibrillations are unorganized contractions. ANSWER: Ectopic pacemaker activity Tachycardia with a heart rate of less than 60 bpm Fibrillations rather than organized contractions Periodic premature contractions of the heart chambers Correct Fibrillations, premature contractions facilitated by ectopic pacemakers, and tachycardias both characterize cardiac arrhythmias. Part C - Life-threatening Cardiac Arrhythmia Which of the following cardiac arrhythmias is associated with immediate, life-threatening danger? Select the best answer. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 13/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Hint 1. The Pumping Action of Which Chambers Ensure Sufficient Tissue Perfusion? Recall the chambers whose pumping action is essential to distributing blood throughout the body and you will reduce your answer choices by half. ANSWER: Ventricular fibrillation Atrial tachycardia Atrial fibrillation Ventricular tachycardia Correct Ventricular fibrillations render the pumping activity of the ventricles impossible, and cardiac arrest ensues. Part D - Identifying Cardiac Arrhythmias in an EKG Label the following images illustrating cardiac arrhythmias. Drag and drop the labels to the appropriate images. Hint 1. What Does a Normal EKG Look Like? Recall what a normal EKG looks like and then compare this image with those of the cardiac arrhythmias. ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 14/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Reset Help Atrial Fibrillation Ventricular Fibrillation Premature Atrial Contraction Ventricular Tachycardia Paroxysmal Atrial Tachycardia Premature Ventricular Contraction Correct Cardiac arrhythmias can be identified based on whether they occur in the atria or in the ventricles and based on the degree of disruption from normal cardiac rhythms. IP: Cardiac Cycle Click on the link or the image below to view an animation on cardiac cycle from Interactive Physiology (IP), then answer the questions to the right. IP: Cardiac Cycle Part A Isovolumetric relaxation and ventricular filling (two phases of the cardiac cycle) take place during __________. Hint 1. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 15/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Both take place during the phase when blood pressure is lowest in the aorta. ANSWER: ventricular systole ventricular diastole Correct Yes, both occur during ventricular diastole when the ventricles are not actively contracting and ejecting blood. Part B Which of the following is correct about the filling of the ventricles? Hint 1. Think of the size of the atria and ventricles. ANSWER: The majority of ventricular filling is caused by contraction of the atria. Most blood flows passively into the ventricles through open AV valves. Correct Yes, most of the ventricular filling is passive; atrial contraction adds just a little more blood. Part C Describe the pressures in the atria and ventricles that would cause the opening of the AV valves. Hint 1. Blood moves from a higher pressure to a lower pressure. ANSWER: Pressure in the ventricles would be greater than in the atria. Pressures in the atria and ventricles would be equal. Pressure in the atria would be greater than the pressure in the ventricles. Correct Yes, higher pressure in the atria than in the ventricles forces the AV valves to open and blood moves into the ventricles. Part D What causes the aortic semilunar valve to close? Hint 1. Remember that blood flows from a higher pressure to a lower pressure. ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 16/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins equal ventricular and aortic pressures higher ventricular pressure than aortic pressure greater pressure in the aorta than in the left ventricle Correct Yes, backflow of blood in the aorta (towards the left ventricle) closes the aortic semilunar valve. Part E Put the phases of the cardiac cycle in the correct order, starting after ventricular filling. Hint 1. If the ventricle is full, what would happen next? ANSWER: isovolumetric contraction, ventricular ejection, isovolumetric relaxation ventricular ejection, ventricular relaxation, isovolumetric contraction isovolumetric relaxation, ventricular ejection, isovolumetric contraction ventricular ejection, isovolumetric contraction, isovolumetric relaxation Correct Yes, the ventricles must contract and eject blood before they relax and fill again. Part F Increased pressure in the ventricles would close what valve(s)? Hint 1. Remember, blood moves from high pressure to low pressure. ANSWER: AV valves only both semilunar and AV valves semilunar valves only Correct Yes, increased pressure in the ventricles would close the AV valves. Art-labeling Activity: The Conducting System of the Heart Identify the structural components of the conducting system of the heart. Part A Drag the labels to identify the structural components of the conducting system of the heart. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 17/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins ANSWER: Reset Help Sinoatrial (SA) node Atrioventricular (AV) node Internodal pathways Bundle branches AV bundle Purkinje fibers Correct Chapter Test - Chapter 20 Question 15 Part A The volume of blood remaining in the ventricle as ventricular diastole begins is called the __________. ANSWER: stroke volume end-systolic volume end-diastolic volume cardiac reserve Correct Chapter Test - Chapter 20 Question 11 Part A The plateau phase of the ventricular action potential is caused by _______. ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 18/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins fast voltage-gated Ca2+ channels opening fast Na+ channels opening slow voltage-gated Ca2+ channels opening slow K+ channels opening Correct Chapter Test - Chapter 20 Question 10 Part A Which of the following correctly lists the order of events in the conducting pathway? ANSWER: SA node, internodal pathway, AV node, AV bundle, bundle branches, Purkinje fibers AV node, internodal pathway, SA node, AV bundle, bundle branches, Purkinje fibers SA node, AV node, internodal pathway, AV bundle, bundle branches, Purkinje fibers SA node, internodal pathway, AV node, AV bundle, bundle branches Correct Chapter Test - Chapter 20 Question 8 Part A The P wave of the electrocardiogram is closely followed by __________. ANSWER: contraction of both atria relaxation of both atria contraction of both ventricles relaxation of the ventricles Correct Chapter Test - Chapter 20 Question 4 Part A https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 19/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins The papillary muscles function to __________. ANSWER: push blood from the atria into the ventricles close the AV valves prevent the AV valves from inverting into the atria eject blood from the ventricles Correct Chapter Test - Chapter 20 Question 18 Part A Which of the following will NOT increase the heart rate? ANSWER: increased sympathetic stimulation of the SA node faster rise of the pacemaker potential increased levels of circulating epinephrine increased parasympathetic stimulation of the SA node Correct Chapter 20 Reading Quiz Question 1 Part A Blood flowing in the vena cava will next enter the __________. ANSWER: right ventricle right atrium left atrium left ventricle Correct Chapter Test - Chapter 20 Question 2 https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 20/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Part A The ____________ follows the coronary sulcus around the heart and supplies blood to the left atrium and ventricle. ANSWER: circumflex artery right coronary artery anterior interventricular artery left coronary artery Correct Art-based Question: The Heart Question 5 Part A Which of the following will receive electrical impulses next after the structure indicated by the red arrow? ANSWER: pacemaker cells apex of the heart auricles of the right and left atria interventricular septum Correct Chapter 20 Reading Quiz Question 8 Part A The wall of the left ventricle is thicker than that of the right and the left ventricle pumps more blood than the right. Are these two statements true or false? ANSWER: https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 21/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Both statements are true. Both statements are false. The first is true; the second is false. The first is false; the second is true. Correct Chapter 20 Reading Quiz Question 6 Part A At rest, the end-systolic volume (ESV) is what percent of the end-diastolic volume (EDV)? ANSWER: 60% 30% 70% 40% Correct Chapter Test - Chapter 20 Question 1 Part A The epicardium is also known as the __________. ANSWER: myocardium parietal pericardium visceral pericardium endocardium Correct Art-based Question: The Heart Question 1 Part A https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 22/23 4/7/24, 12:38 AM Ch20 - Homework - the Heart ~35 mins Identify the specific serous membrane layer at the end of the arrow. ANSWER: visceral peritoneum visceral pericardium visceral pleura parietal pericardium Correct Chapter Test - Chapter 20 Question 17 Part A Which of the following factors will decrease cardiac output? ANSWER: increased venous return sympathetic activation increased preload stimulation of the vagus nerve Correct Score Summary: Your score on this assignment is 90.0%. You received 7.74 out of a possible total of 8.6 points. https://session.masteringaandp.com/myct/assignmentPrintView?assignmentID=10505307 23/23