Pathophysiology Exam Test 2 Practice VERIFIED SOLUTIONS 2023//2024

Pathophysiology Exam Test 2 Practice VERIFIED SOLUTIONS 2023//2024 Which of the following valves directs blood flow from the left atrium to the left ventricle? A. Mitral B. Tricuspid C. Aortic D. Pulmonic - ANSWER A. Mitral The layer of squamous cells that lines the cardiac chambers and valves is called the: A. myocardium B. endocardium C. epicardium D. Pericardium - ANSWER B. endocardium How much does the atrial kick increase the blood volume? A. 5%-10% B. 10%-15% C. 15%-20% D. 20%-25% - ANSWER C. 15%-20% Which of the following waves corresponds with the AV valve bulging during ventricular contraction? A. A wave B. C wave C. D wave D. V wave - ANSWER B. C wave (The A wave corresponds with atrial contraction, the C wave corresponds with the AV valve bulging during ventricular contraction, and the V wave corresponds to atrial filling. There is no D wave. What portions of the heart does the left anterior descending branch supply? A. Septal, anterior and apical B. Lateral and Posterior C. Lateral and septal D. Posterior and apical - ANSWER A. Septal, anterior, and apical What is the name for the arrangement in which separate cells of the myocardium can function together? A. Autoregulation B. Syncytium C. Ischemia D. Myocyte - ANSWER B. Syncytium The structure that is composed of six polypeptide chains, two heavy chains, and four light chains is called: A. actin B. tropomyosin C. troponin D. myosin - ANSWER D. myosin Which electrolyte is necessary for muscle contraction? A. Na+ B. K+ C. Ca++ D. Mg++ - ANSWER C. Ca++ Which of the following statments is true regarding muscle contraction? A. Calcium removal from the cytoplasm causes contraction. B. Calcium entry into the cytoplasm causes relaxation. C. Cardiac myocytes are terminally differentiated. D. Contraction of cardiac muscle results from lengthening of sarcomeres. - ANSWER C. Cardiac myocytes are terminally differentiated. Which of the following phases of cardiac action potentials is causes by closure of the fast sodium channels? A. Phase 0 B. Phase1 C. Phase 2 D. Phase 3 - ANSWER B. Phase 1 Which of the following refers to intermittent, spontaneous generation of action potentials? A. Rhythmicity B. Relative refractory C. Antiarrhythmics D. Repolarization - ANSWER A. Rhythmicity Which of the following is not a normal excitation pathway? A. AV node B. SA node C. Bundle of His D. VA node - ANSWER D. VA node Which of the following statements is true regarding the vagus nerves? A. The left vagus nerve supplies the SA node. B. The right vagus nerve supplies both the SA and AV nodes. C. Parasympathetic nerves innervate all of the ventricles. D. Parasympathetic nerve stimulation reduces the heart rate. - ANSWER D. Parasympathetic nerve stimulation reduces the heart rate. Which of the following terms refers to increased speed of conduction? A. Dromotropic B. Chronotropic C. Inotropic D. Acetylcholine - ANSWER A. Dromotropic (Chronotropic refers to increased heart rate, inotropic refers to increased contractile force) Which of the following waves on the ECG is representative of depolarization of the lateral walls? A. Q wave B. R wave C. S wave D. T wave - ANSWER C. S wave The part of the cardiac cycle in which the cardiac muscle obtains its oxygen and gets rid of waste products is the: A. Systole B. Diastole C. Isovolumic Contraction D. Ventricular ejection - ANSWER B. Diastole (the heart muscle relaxes and allows blood to flow through it as it relaxes and fills passively during diastole) Myocytes leak the enzyme creatine kinase (CK) into the blood stream in response to : A. cell growth B. cell maturation C. cell ischemia and death D. all of the above - ANSWER C. cell ischemia and death The echocardiogram is especially useful in the measurement of the: A. coronary blood flow and location of obstructions. B. Structures and motion of the heart within the chest. C. Structures and function of the lungs. D. All of the above. - ANSWER B. Structures and motion of the heart within the chest. Atherosclerosis predisposes to a number of processes, precipitating myocardial ischemia. These processes include: A. coronary dilation B. thrombus formation C. hemorrhage D. ventricular dysrhythmia - ANSWE