A&P 2 CH 19
During ventricular contraction A. the semilunar valves open and the AV valves close. B. only the semilunar valves close. C. the semilunar valves close and the AV valves open. D. only the AV valves open. E. only the AV valves close.
A
Norepinephrine is considered a positive chronotropic agent because it causes A. an increase in the firing rate of SA node cells. B. thyroid hormone to have a steadying effect on heart activity. C. heart cell membrane potentials to become more positive during action potentials. D. more forceful contractions during each heart rate. E. less calcium to enter heart cells, which leads to lower risk of heart attack.
A
Someone with tachyarrhythmia would be expected to show an abnormally A. small Q-T interval. B. large P-R interval. C. large R-R interval. D. high amplitude P wave.
A
The papillary muscles attach to the cusps of the atrioventricular valves by means of the A. tendinous cords. B. pectinate muscles. C. conus arteriosus. D. trabeculae carneae. E. tricuspid valve.
A
To initiate a cardiac muscle cell contraction, calcium A. binds to troponin. B. binds to actin. C. binds to the Z-disc. D. binds to calmodulin. E. binds to tropomyosin.
A
Which correctly describes the heart's apex? A. Projects slightly anteroinferiorly toward the left side of the body B. Projects slightly posteroinferiorly toward the left side of the body C. Projects slightly posteroinferiorly toward the right side of the body D. Projects slightly posteroinferiorly toward the midline of the body E. Projects slightly anteroinferiorly toward the right side of the body
A
Which type of muscle cell exhibits a longer refractory period? A. Cardiac muscle cell B. Skeletal muscle cell
A
Chronotropic
A chemical that alters heart rate is known as a(n) __________ agent
Which describes the endocardium? A: Has single layer of epithelium B: Has layer of areolar connective tissue C: Epithelial cells are squamous D: Epithelial cells are cuboidal E: Has layer of adipose connective tissue F: Has patches of myocardium
A, B, C
Which are functions performed by the fibrous skeleton of the heart? A. Separates the atria and ventricles B. Anchors the heart valves C. Provides electrical insulation between the atria and ventricles D. Provides the framework for the attachment of the myocardium E. None of these are true functions of the fibrous skeleton of the heart
A, B, C, D
Blood moves into and then out of a heart chamber because A. by the control of valve openings and closures. B. it moves along its pressure gradient, and that gradient depends on contraction and relaxation during the cardiac cycle. C. All of the choices are correct. D. the veins and arteries constrict and dilate to propel and attract blood.
B
Blood moves into and then out of a heart chamber because A. it is under constant pressure, but its movement is dictated by the control of valve openings and closures. B. It moves along its pressure gradient, and that gradient depends on contraction and relaxation during the cardiac cycle. C. the veins and arteries constrict and dilate to propel and attract blood. D. All of the choices are correct.
B
Which action leads to the closure of the right atrioventricular valve? A. Contraction of the right atrium B. Contraction of the left atrium C. Contraction of the right ventricle D. Relaxation of the right ventricle E. Relaxation of the left atrium
C
Cardiac output is the amount of blood that is pumped A. by a single ventricle in one hour. B. by both ventricles in one hour. C. by both ventricles in one minute. D. by a single ventricle in one minute. E. by the left ventricle into the aorta in one beat.
D
During the S-T segment, what is occurring within cardiac muscle cells? A. Sodium is rapidly diffusing out of atrial muscle cells. B. Sodium channels are beginning to open in ventricular cells and calcium is entering through slow channels in atrial cells. C. Potassium is entering atrial cells and sodium is leaving ventricular cells. D. Calcium is entering and potassium is leaving ventricular cells.
D
How many half-moon shaped, pocketlike cusps are found in each semilunar valve? A. 1 B. 6 C. 4 D. 3 E. 2
D
The fossa ovalis appears just above the opening of the coronary sinus within the A. left atrium. B. left ventricle. C. right ventricle. D. right atrium.
D
The pericardial cavity is between the A. fibrous and serous layers of the pericardium. B. heart muscle and serous pericardium. C. parietal and myocardial layers of the fibrous pericardium. D. visceral and parietal layers of the serous pericardium.
D
The shutting of the semilunar valves occurs during which phase? A. Ventricular ejection B. Isovolumetric contraction C. Atrial contraction and ventricular filling D. Isovolumetric relaxation E. Late ventricular diastole
D
The term "epicardium" is another name for the A. mediastinum. B. myocardium. C. external layer of the fibrous pericardium. D. visceral layer of the serosal pericardium. E. parietal layer of the serosal pericardium.
D
The units for perfusion of blood are typically A. millimiters per hour per kilogram. B. liters per gram. C. grams per minute. D. milliliters per minute per gram. E. beats per minute per gram.
D
Vagal tone refers to the A. increasing of the heart rate above its inherent rhythm by parasympathetic stimulation. B. increasing of the heart rate above its inherent rhythm by sympathetic stimulation. C. decreasing of the heart rate below its inherent rhythm by sympathetic stimulation. D. decreasing of the heart rate below its inherent rhythm by parasympathetic stimulation.
D
Which layer is made of dense irregular connective tissue? A. Myocardium B. Endocardium C. Epicardium D. Fibrous pericardium E. Serous pericardium
D
Which of the following would cause a decrease in cardiac output? A. An increase in venous return B. An increase in heart rate C. Addition of positive inotropic agents D. An increase in afterload
D
Septum
Deep to the interventricular sulci is the thick muscular wall that divides the left and right ventricles, known as the interventricular ________.
Cardiac output equals the A. cardiac reserve minus the stroke volume. B. stroke volume divided by heart rate. C. blood pressure multiplied by heart rate. D. end diastolic volume minus end systolic volume. E. heart rate multiplied by stroke volume.
E
In an ECG, what does the T wave represent? A. Closure of the AV valves B. Depolarization of the right ventricle C. Depolarization of the left ventricle D. Depolarization of the atria E. Repolarization of the ventricles
E
The function of the coronary sinus is to A. shunt blood from the right atrium to the left atrium. B. guide the aorta out of the heart. C. connect the top and bottom halves of the heart. D. guide the inferior vena cava into the right atrium. E. take blood from the coronary circulation to the right atrium.
E
Small
The _______________ cardiac vein travels alongside the right marginal artery.
Auricle
The anterior part of each atrium is a flaplike extension called a(n) _______________.
Parasympathetic and sympathetic influence on heart rate is controlled by reflexes. True False
True
Parasympathetic innervation influences the heart rate, but generally tends to have no direct effect on the force of contractions. True False
True
SA nodal cells are autorhythmic True False
True
The main functions of the cardiovascular system include the transport and exchange of respiratory gases, nutrients, and wastes throughout the body. True False
True
The receiving chambers of the heart are the atria, and the forcefully pumping chambers of the heart are the ventricles. True False
True
Sympathetic
________________ innervation increases the rate and the force of heart contraction.
During a cardiac cycle, how many of the four chambers contract at any one time? A. 1 B. 2 C. 4 D. Highly variable, depending on the heart beat rate E. None of the choices is correct.
B
During the plateau phase of a cardiac muscle cell's action potential, the membrane stays A. hyperpolarized as potassium enters and calcium exits. B. depolarized as potassium exits and calcium enters. C. hyperpolarized as sodium and calcium exit. D. depolarized as potassium enters and calcium exits. E. repolarized as sodium enters and calcium exits.
B
The foramen ovale of the fetal heart is an opening in the A. tetralogy of Fallot. B. interatrial septum. C. aorticopulmonary septum. D. fossa ovalis. E. interventricular septum.
B
Which of the cardiovascular system's circuits has deoxygenated blood in its arteries? A. Systemic circuit B. Pulmonary circuit C. Coronary circuit D. Visceral circuit
B
Once an SA nodal cell reaches threshold, the depolarization phase occurs during which A. potassium comes in through fast voltage-gated channels. B. sodium moves out through slow voltage-gated channels. C. calcium comes in through fast voltage-gated channels. D. potassium moves out through fast voltage-gated channels. E. calcium moves out through slow voltage-gated channels.
C
The metabolic pathways of cardiac muscle make it extremely susceptible to heart attack, because it uses such a variety of fuel sources. A. relatively resistant to heart attack, because it uses exclusively anaerobic metabolism. B. somewhat susceptible to heart attack, because it relies so exclusively on aerobic metabolism. C. relatively resistant to heart attack, because it has a great D. capacity to accrue oxygen debt. E. somewhat susceptible to heart attack, because it has so few mitochondria.
C
What would you expect a cardiologist to recommend if there was substantial occlusion to a patient's left coronary artery but not the right coronary artery? A. Because there are multiple alternate paths for blood delivery, the cardiologist would not intervene. B. Because this is a relatively small, unimportant artery, the cardiologist would not intervene. C. Because this is an important artery, and alternate vascular paths are inadequate, the cardiologist would treat the condition. D. Because occlusions require blood to be moved under greater pressure, the cardiologist would prescribe drugs to raise blood pressure.
C
Which vein drains the posterior aspect of the ventricles of the heart? A. Great cardiac vein B. Circumflex vein C. Middle cardiac vein D. Small cardiac vein
C
What is the sequence of events in the transmission of an impulse through the heart muscle? A. AV node B. AV bundle C. SA node D. Through the atria E. Through the ventricles F. Bundle branches g: Purkinje fibers
C, D, A, B, F, G, E
Arteries carry blood toward the heart, while veins carry blood away from the heart. True False
False
Edema
If the stroke volume is unequal between the left and right ventricles, ________ may occur, which is excess fluid surrounding or within cells.
Isovolumetric Contraction
The beginning of contraction in the ventricles is called _________ _________.
Anastomoses
The connections shared by arteries that allow them to shunt blood from one artery to another are called _________________.
SA
The heartbeat is initiated by the cells of the _______________ node
Ventricles
The inferior chambers of the heart are called ________________.
Apex
The inferior, conical end of the heart is called the _______________.
Myocardium
The middle layer of the heart wall that is made of cardiac muscle tissue is the ________________.
Desmosomes
The numerous ________________ within the intercalated discs prevent cardiac muscle fibers from pulling apart.
Audtorhythmicity
The property that allows the heart to initiate each heartbeat itself is called __________________.
After-load
The resistance in arteries to the ejection of blood by the heart is known as _________.
Ischemia
The term used to describe the inadequate blood flow to a structure caused by obstruction of the blood supply is _________________.
Refractory
The time that starts when a muscle cell is depolarized and ends when it is able to be restimulated is the __________ period.
Anterior interventricular
This artery is sometimes referred to as the "widowmaker" because blockage of it often leads to fatal heart attack. It serves the front of the heart and is more formally called the (2 words) _________ __________ artery.
