ECG Exam 1 with all Correct & 100% Verified Answers |
Latest Version |Already Graded A+
__________ is the period during which a heart chamber is contracting and blood is being ejected.
✔Correct Answer-systole
The thick, muscular middle layer of the heart wall that contains the atrial and ventricular muscle
fibers necessary for contraction is the __________. ✔Correct Answer-myocardium
The ______ chambers receive blood from the vena cava and coronary sinus. ✔Correct Answer-
right atrium
The inferior outer surface of the heart is also called the _____ surface. ✔Correct Answer-
diaphragmatic
The _____ are the heart chambers that pump blood. ✔Correct Answer-ventricles
_____ is the period of relaxation during which a heart chamber is filling. ✔Correct Answer-Diastole
Blood pressure is the result of cardiac output and peripheral vascular resistance. ✔Correct Answer-
true
Stimulation of beta-adrenergic receptor sites will result in peripheral vasoconstriction. ✔Correct
Answer-false
Sensors in the internal carotid arteries and aortic arch that detect changes in the concentration of
hydrogen ions (pH), oxygen, and carbon dioxide in the blood ✔Correct Answer-Chemoreceptors
Space between the lungs that contains the heart, great vessels, trachea, and esophagus, among
other structures ✔Correct Answer-Mediastinum
Specialized nerve tissue located in the internal carotid arteries and the aortic arch that detect
changes in blood pressure ✔Correct Answer-Baroreceptors
Electrolyte very important in cardiac muscle contraction. ✔Correct Answer-calcium
Amount of blood flowing into the right atrium each minute from the systemic circulation ✔Correct
Answer-Venous return
Term used to refer to distinct conditions caused by a similar sequence of pathologic events—a
temporary or permanent blockage of a coronary artery ✔Correct Answer-Acute coronary
syndromes
Typically results when the heart's demand for oxygen exceeds its supply from the coronary
circulation ✔Correct Answer-Myocardial ischemia
A negative _____ effect refers to a decrease in heart rate. ✔Correct Answer-Chronotropic
, A buildup of excess blood or fluid in the pericardial space can cause cardiac _____. ✔Correct
Answer-Tamponade
List two factors that may affect the heart's efficiency as a pump. ✔Correct Answer-Abnormalities of
cardiac muscle, the valves, or the conduction system.
Name the valve that separates the right ventricle from the right atrium. ✔Correct Answer-Tricuspid
valve.
Define systole. ✔Correct Answer-Contraction or the ejection of blood from a chamber of the heart.
What is meant by the term ejection fraction? ✔Correct Answer-Ejection fraction is the percentage
of blood pumped out of a heart chamber with each contraction. Each ventricle holds about 150 mL
when it is full; they normally eject only about half this volume (70 to 80 mL) with each contraction.
Explain the Frank-Starling law of the heart. ✔Correct Answer-According to the Frank-Starling law of
the heart, to a point, the greater the volume of blood in the heart during diastole, the more forceful
the cardiac contraction, and the more blood the ventricle will pump (stroke volume). This is
important so that the heart can adjust its pumping capacity in response to changes in venous return,
such as during exercise. If, however, the ventricle is stretched beyond its physiologic limit, cardiac
output may fall because of volume overload and overstretching of the muscle fibers.
A patient has a heart rate of 80 beats/min. His stroke volume is 70 mL/beat. Is his cardiac output
normal, decreased, or increased? ✔Correct Answer-Output is normal.Stroke volume = 70
mL/beatHeart rate = 80 beats/minuteSV ´ HR = CO70 mL/beat ´ 80 beats/min = 5600 mL/min = 5.6
L/minCardiac output = normal (normal is between 4 and 8 L/min)
Briefly describe parasympathetic innervation of the heart. ✔Correct Answer-Parasympathetic
(inhibitory) nerve fibers supply the sinoatrial node, atrial muscle, and the atrioventricular junction of
the heart by the vagus nerves.
The right atrium receives blood low in oxygen from three vessels. Name them. ✔Correct Answer-
Superior vena cava, inferior vena cava, and coronary sinus.
List three types of sympathetic (adrenergic) receptor sites. ✔Correct Answer-There are five main
types of sympathetic (adrenergic) receptors: alpha1, alpha2, beta1, beta2, and dopamine (or
dopaminergic).
What factors affect afterload? ✔Correct Answer-Afterload is the pressure or resistance against
which the ventricles must pump to eject blood. Afterload is influenced by the following: arterial
blood pressure, the ability of the arteries to become stretched (arterial distensibility), and arterial
resistance.
Define atrial kick. ✔Correct Answer-At the end of ventricular diastole, both atria simultaneously
contract to eject 10% to 30% more blood into the ventricles.
What effects can be expected from sympathetic stimulation of the heart? ✔Correct Answer-
Sympathetic stimulation of the heart results in increased heart rate, force of contraction, conduction
velocity, blood pressure, and cardiac output.
Latest Version |Already Graded A+
__________ is the period during which a heart chamber is contracting and blood is being ejected.
✔Correct Answer-systole
The thick, muscular middle layer of the heart wall that contains the atrial and ventricular muscle
fibers necessary for contraction is the __________. ✔Correct Answer-myocardium
The ______ chambers receive blood from the vena cava and coronary sinus. ✔Correct Answer-
right atrium
The inferior outer surface of the heart is also called the _____ surface. ✔Correct Answer-
diaphragmatic
The _____ are the heart chambers that pump blood. ✔Correct Answer-ventricles
_____ is the period of relaxation during which a heart chamber is filling. ✔Correct Answer-Diastole
Blood pressure is the result of cardiac output and peripheral vascular resistance. ✔Correct Answer-
true
Stimulation of beta-adrenergic receptor sites will result in peripheral vasoconstriction. ✔Correct
Answer-false
Sensors in the internal carotid arteries and aortic arch that detect changes in the concentration of
hydrogen ions (pH), oxygen, and carbon dioxide in the blood ✔Correct Answer-Chemoreceptors
Space between the lungs that contains the heart, great vessels, trachea, and esophagus, among
other structures ✔Correct Answer-Mediastinum
Specialized nerve tissue located in the internal carotid arteries and the aortic arch that detect
changes in blood pressure ✔Correct Answer-Baroreceptors
Electrolyte very important in cardiac muscle contraction. ✔Correct Answer-calcium
Amount of blood flowing into the right atrium each minute from the systemic circulation ✔Correct
Answer-Venous return
Term used to refer to distinct conditions caused by a similar sequence of pathologic events—a
temporary or permanent blockage of a coronary artery ✔Correct Answer-Acute coronary
syndromes
Typically results when the heart's demand for oxygen exceeds its supply from the coronary
circulation ✔Correct Answer-Myocardial ischemia
A negative _____ effect refers to a decrease in heart rate. ✔Correct Answer-Chronotropic
, A buildup of excess blood or fluid in the pericardial space can cause cardiac _____. ✔Correct
Answer-Tamponade
List two factors that may affect the heart's efficiency as a pump. ✔Correct Answer-Abnormalities of
cardiac muscle, the valves, or the conduction system.
Name the valve that separates the right ventricle from the right atrium. ✔Correct Answer-Tricuspid
valve.
Define systole. ✔Correct Answer-Contraction or the ejection of blood from a chamber of the heart.
What is meant by the term ejection fraction? ✔Correct Answer-Ejection fraction is the percentage
of blood pumped out of a heart chamber with each contraction. Each ventricle holds about 150 mL
when it is full; they normally eject only about half this volume (70 to 80 mL) with each contraction.
Explain the Frank-Starling law of the heart. ✔Correct Answer-According to the Frank-Starling law of
the heart, to a point, the greater the volume of blood in the heart during diastole, the more forceful
the cardiac contraction, and the more blood the ventricle will pump (stroke volume). This is
important so that the heart can adjust its pumping capacity in response to changes in venous return,
such as during exercise. If, however, the ventricle is stretched beyond its physiologic limit, cardiac
output may fall because of volume overload and overstretching of the muscle fibers.
A patient has a heart rate of 80 beats/min. His stroke volume is 70 mL/beat. Is his cardiac output
normal, decreased, or increased? ✔Correct Answer-Output is normal.Stroke volume = 70
mL/beatHeart rate = 80 beats/minuteSV ´ HR = CO70 mL/beat ´ 80 beats/min = 5600 mL/min = 5.6
L/minCardiac output = normal (normal is between 4 and 8 L/min)
Briefly describe parasympathetic innervation of the heart. ✔Correct Answer-Parasympathetic
(inhibitory) nerve fibers supply the sinoatrial node, atrial muscle, and the atrioventricular junction of
the heart by the vagus nerves.
The right atrium receives blood low in oxygen from three vessels. Name them. ✔Correct Answer-
Superior vena cava, inferior vena cava, and coronary sinus.
List three types of sympathetic (adrenergic) receptor sites. ✔Correct Answer-There are five main
types of sympathetic (adrenergic) receptors: alpha1, alpha2, beta1, beta2, and dopamine (or
dopaminergic).
What factors affect afterload? ✔Correct Answer-Afterload is the pressure or resistance against
which the ventricles must pump to eject blood. Afterload is influenced by the following: arterial
blood pressure, the ability of the arteries to become stretched (arterial distensibility), and arterial
resistance.
Define atrial kick. ✔Correct Answer-At the end of ventricular diastole, both atria simultaneously
contract to eject 10% to 30% more blood into the ventricles.
What effects can be expected from sympathetic stimulation of the heart? ✔Correct Answer-
Sympathetic stimulation of the heart results in increased heart rate, force of contraction, conduction
velocity, blood pressure, and cardiac output.
