Chapter 17: Function Of The Heart
Anatomy 2, Chapter 17
Questions and Answers
- 1.
Systole and diastole describe the function of the
- A.
Pericardium
- B.
SA node
- C.
Myocardium
- D.
Mediastinum
Correct Answer
C. MyocardiumExplanation
Systole and diastole refer to the contraction and relaxation of the heart, respectively. The myocardium is the muscular tissue of the heart responsible for these actions. It contracts during systole to pump blood out of the heart and relaxes during diastole to allow the chambers to fill with blood. Therefore, the myocardium is directly involved in the function of systole and diastole.Rate this question:
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- 2.
During atrial systole, the
- A.
AV valves are closed
- B.
Ventricles are relaxed
- C.
Ventricles are in systole
- D.
Semilunar valves are open
Correct Answer
B. Ventricles are relaxedExplanation
During atrial systole, the atria contract to push blood into the ventricles. At this stage, the AV valves (tricuspid and mitral valves) are closed to prevent the backflow of blood from the ventricles to the atria. The ventricles are relaxed during this phase, as they have already pumped blood out during the previous ventricular systole. The semilunar valves (pulmonary and aortic valves) are closed at this stage to prevent blood from flowing back into the ventricles. Therefore, the correct answer is "ventricles are relaxed".Rate this question:
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- 3.
What happens during ventricular diastole?
- A.
The ventricles are filling with blood
- B.
All semilunar valves are open
- C.
Both AV valves are closed
- D.
Blood is pumped to the lungs and systemic circulation
Correct Answer
A. The ventricles are filling with bloodExplanation
During ventricular diastole, the ventricles of the heart are relaxed and filling with blood. This is the phase of the cardiac cycle when the heart is at rest and preparing for the next contraction. Both atrioventricular (AV) valves, which separate the atria from the ventricles, are closed to prevent blood from flowing back into the atria. The semilunar valves, which separate the ventricles from the arteries, are also closed during this phase. Blood is not being pumped to the lungs or systemic circulation during ventricular diastole, as that occurs during ventricular systole.Rate this question:
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- 4.
Which of the following is the most likely consequence of a very rapid heart rate?
- A.
Decreased ventricular filling (with blood)
- B.
Failure of the AV valves to open
- C.
Failure of the SA node to fire
Correct Answer
A. Decreased ventricular filling (with blood)Explanation
A very rapid heart rate can lead to decreased ventricular filling with blood because when the heart beats too quickly, there is not enough time for the ventricles to fully fill with blood before the next contraction. This can result in a decrease in the amount of blood pumped out of the heart with each beat, leading to a decreased cardiac output.Rate this question:
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- 5.
Which of the following does not happen to a ventricle?
- A.
Activation of the beta1 adrenergic receptors
- B.
Discharge of sympathetic nerves
- C.
Discharge of the vagal nerve
- D.
Binding of norepinephrine to its receptor
Correct Answer
C. Discharge of the vagal nerveExplanation
The discharge of the vagal nerve does not happen to a ventricle. The vagal nerve, also known as the parasympathetic nerve, is responsible for slowing down the heart rate and reducing the force of contractions. In contrast, the other options mentioned, such as activation of beta1 adrenergic receptors, discharge of sympathetic nerves, and binding of norepinephrine to its receptor, all involve sympathetic activation, which increases heart rate and contractility.Rate this question:
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- 6.
Which of the following is most likely to relieve an anxiety-induced tachycardia?
- A.
Vagolytic drug
- B.
Beta1 adrenergic agonist
- C.
Sympathomimetic
- D.
Beta1 adrenergic blocker
Correct Answer
D. Beta1 adrenergic blockerExplanation
A beta1 adrenergic blocker is most likely to relieve an anxiety-induced tachycardia. Tachycardia refers to a rapid heartbeat, and anxiety can often cause an increase in heart rate. Beta1 adrenergic blockers, also known as beta blockers, work by blocking the effects of adrenaline on the beta1 receptors in the heart. By doing so, they can reduce the heart rate and blood pressure, helping to relieve tachycardia.Rate this question:
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- 7.
Which of the following is responsible for the Starling effect?
- A.
Sympathetic nerve firing
- B.
Vagal discharge
- C.
Activation of the beta1 adrenergic receptors
- D.
End diastolic volume (EDV)
Correct Answer
D. End diastolic volume (EDV)Explanation
The Starling effect refers to the phenomenon where an increase in end diastolic volume (EDV) results in a more forceful contraction of the heart and an increase in stroke volume. EDV is the volume of blood in the ventricles at the end of diastole, just before contraction. As the ventricles fill with more blood, the myocardial fibers are stretched, leading to a more forceful contraction and an increased stroke volume. This effect allows the heart to adapt and pump a greater volume of blood when there is an increase in venous return or preload.Rate this question:
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- 8.
Which of the following is most likely to increase stroke volume?
- A.
A (+) inotrpic drug
- B.
A vagolytic drug
- C.
A (-) chronotropic drug
- D.
A beta1 adrenergic blocker
Correct Answer
A. A (+) inotrpic drugExplanation
A (+) inotropic drug is most likely to increase stroke volume. Inotropic drugs enhance the force of contraction of the heart muscle, leading to an increase in the amount of blood pumped out of the heart with each heartbeat. This increased force of contraction results in an increased stroke volume, which is the amount of blood ejected from the heart per beat. Therefore, a (+) inotropic drug would be expected to increase stroke volume.Rate this question:
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- 9.
Which of the following is most likely to increase ejection fraction?
- A.
Activation of beta1 adrenergic receptors
- B.
Vagal discharge
- C.
Blockade of beta1 adrenergic receptors
- D.
Blockade of the muscarinic receptors
Correct Answer
A. Activation of beta1 adrenergic receptorsExplanation
Activation of beta1 adrenergic receptors is most likely to increase ejection fraction. Beta1 adrenergic receptors are primarily found in the heart and their activation leads to an increase in heart rate and contractility. This increased contractility allows for a larger volume of blood to be pumped out of the heart with each contraction, leading to an increase in ejection fraction.Rate this question:
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- 10.
Which of the following is the same as end dialostic volume?
- A.
Stroke volume
- B.
Cardiac output
- C.
Preload
- D.
Cardiac reserve
Correct Answer
C. PreloadExplanation
Preload refers to the volume of blood in the ventricles at the end of diastole, just before contraction. It represents the amount of blood that the heart has to pump out with each beat. End diastolic volume is the same as preload because it refers to the volume of blood in the ventricles at the end of diastole. Therefore, preload is the correct answer.Rate this question:
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- 11.
What terms refers to the amount of blood pumped by the ventricle in one boat?
- A.
Cardiac output
- B.
Blood volume
- C.
Hematocrit
- D.
Stroke volume
Correct Answer
D. Stroke volumeExplanation
Stroke volume refers to the amount of blood pumped by the ventricle in one beat. It is a measure of the volume of blood ejected from the heart with each contraction of the ventricles. Cardiac output, on the other hand, refers to the total amount of blood pumped by the ventricle in one minute and is calculated by multiplying stroke volume by heart rate. Blood volume refers to the total volume of blood in the body, and hematocrit is the percentage of red blood cells in the blood.Rate this question:
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- 12.
Which term refers to the amount of blood pumped by the heart in one minute?
- A.
Stroke volume
- B.
Cardiac output
- C.
Starling's law of the heart
- D.
Inotropic effect
Correct Answer
B. Cardiac outputExplanation
Cardiac output refers to the amount of blood pumped by the heart in one minute. It is a measure of the heart's efficiency in delivering oxygenated blood to the body's tissues. Cardiac output is calculated by multiplying the heart rate (number of beats per minute) by the stroke volume (amount of blood pumped with each beat). It is an important parameter in assessing cardiovascular health and can be influenced by various factors such as exercise, stress, and certain medical conditions.Rate this question:
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- 13.
Sympathetic nerve stimulation of the myocardium
- A.
Causes a (+) inotropic effect
- B.
Decreases cardiac output
- C.
Decreases heart rate
- D.
Decreases stroke volume
Correct Answer
A. Causes a (+) inotropic effectExplanation
Sympathetic nerve stimulation of the myocardium causes a (+) inotropic effect. This means that it increases the force of contraction of the heart muscle. When the sympathetic nervous system is activated, it releases norepinephrine, which binds to beta-adrenergic receptors on the myocardium. This leads to an increase in intracellular calcium levels, which in turn enhances the contractility of the heart. As a result, the heart pumps blood more forcefully, leading to an increase in the strength of the heartbeat.Rate this question:
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- 14.
Vagal stimulation to the heart causes
- A.
A (+) inotrpoic effect
- B.
Heart rate to slow
- C.
Cardiac output to increase
- D.
Stroke volume to increase
Correct Answer
B. Heart rate to slowExplanation
Vagal stimulation to the heart activates the parasympathetic nervous system, specifically the vagus nerve. This stimulation leads to a decrease in heart rate, as the vagus nerve releases acetylcholine, which slows down the firing rate of the sinoatrial (SA) node, the natural pacemaker of the heart. Therefore, the correct answer is "heart rate to slow."Rate this question:
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- 15.
Excess vagal stimulation to the SA node is most likely to cause
- A.
Hypertension
- B.
Bradycardia
- C.
Tachycardia
- D.
Anemia
Correct Answer
B. BradycardiaExplanation
Excess vagal stimulation to the SA node can cause bradycardia. The vagus nerve, which is part of the parasympathetic nervous system, innervates the SA node and slows down the heart rate. When there is excessive stimulation of the vagus nerve, it can lead to a decrease in heart rate, resulting in bradycardia. This can happen in certain medical conditions or due to certain medications that increase vagal tone. Hypertension, tachycardia, and anemia are not directly caused by excess vagal stimulation to the SA node.Rate this question:
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- 16.
Which of the following is descriptive of the vagus nerve?
- A.
"fight or flight"
- B.
Parasympathetic
- C.
Sympathetic
- D.
Adrenergic
Correct Answer
B. ParasympatheticExplanation
The vagus nerve is a part of the parasympathetic nervous system, which is responsible for the body's rest and digest response. It helps regulate various bodily functions such as heart rate, digestion, and respiratory rate. The terms "fight or flight," sympathetic, and adrenergic are not descriptive of the vagus nerve, as they are associated with the sympathetic nervous system and the release of adrenaline in response to stress or danger.Rate this question:
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- 17.
Heart rate and stroke volume determine
- A.
Hemotocrit
- B.
Total blood volume
- C.
Cardiac output
- D.
The size of the heart valves
Correct Answer
C. Cardiac outputExplanation
Heart rate and stroke volume are two important factors that determine cardiac output. Heart rate refers to the number of times the heart beats per minute, while stroke volume refers to the amount of blood pumped out of the heart with each beat. Cardiac output is the total volume of blood pumped by the heart in one minute, and it is calculated by multiplying the heart rate by the stroke volume. Therefore, heart rate and stroke volume directly affect cardiac output.Rate this question:
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- 18.
A drug (i.e., atropine) that blocks the vagus nerve
- A.
Stops the heart
- B.
Increases the heart rate
- C.
Decreases cardiac output
- D.
Decreases stroke volume
Correct Answer
B. Increases the heart rateExplanation
Atropine is a drug that blocks the vagus nerve, which is responsible for slowing down the heart rate. By blocking the vagus nerve, atropine prevents its inhibitory effect on the heart, leading to an increase in heart rate. Therefore, the correct answer is that atropine increases the heart rate.Rate this question:
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- 19.
Activation of the muscarinic receptors by acetylcholine
- A.
Increases myocardial contractile force
- B.
Causes a (+) chronotropic effect
- C.
Increases cardiac output
- D.
Slows heart rate
Correct Answer
D. Slows heart rateExplanation
Activation of muscarinic receptors by acetylcholine slows heart rate. Muscarinic receptors are found in the parasympathetic nervous system, which is responsible for regulating the heart rate. When these receptors are activated, it leads to a decrease in heart rate, known as a negative chronotropic effect. This is due to the inhibitory actions of the parasympathetic nervous system on the heart, which helps to balance the sympathetic nervous system's stimulatory effects. Therefore, the correct answer is that activation of muscarinic receptors by acetylcholine slows heart rate.Rate this question:
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- 20.
Decreased blood flow through the coronary arteries is most likely to cause
- A.
Valve damage
- B.
Pulmonary edema
- C.
Angina pectoris
- D.
Bradycardia
Correct Answer
C. Angina pectorisExplanation
Decreased blood flow through the coronary arteries can lead to a reduced supply of oxygen and nutrients to the heart muscle. This can cause chest pain known as angina pectoris. Angina occurs when the heart does not receive enough blood and oxygen to meet its demands, usually during physical activity or periods of emotional stress. It is characterized by a squeezing or pressure-like sensation in the chest, which may radiate to the arms, neck, jaw, or back. Angina pectoris is a common symptom of coronary artery disease, where the arteries that supply blood to the heart become narrowed or blocked.Rate this question:
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- 21.
This term refers to a heart rate of fewer that 60 beats/min
- A.
Bradycardia
- B.
Heart block
- C.
Fight-or-flight response
- D.
Tachycardia
Correct Answer
A. BradycardiaExplanation
Bradycardia refers to a heart rate of fewer than 60 beats per minute. This condition occurs when the heart beats slower than normal, which can be caused by various factors such as certain medications, heart disease, or an imbalance in the electrical signals that control the heart. Bradycardia can lead to symptoms like dizziness, fatigue, and shortness of breath. Treatment options may include medication, pacemaker implantation, or addressing the underlying cause of the condition.Rate this question:
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- 22.
Vagal stimulation on the heart
- A.
Increases the force of myocardial contraction
- B.
Increases the amount of blood that flows into the heart from the vena cava
- C.
Causes tachycardia
- D.
Slows the heart rate
Correct Answer
D. Slows the heart rateExplanation
Vagal stimulation on the heart slows the heart rate. The vagus nerve, also known as the parasympathetic nervous system, is responsible for regulating the heart rate. When the vagus nerve is stimulated, it releases acetylcholine, which slows down the electrical conduction in the heart and decreases the heart rate. This is known as vagal bradycardia.Rate this question:
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- 23.
Which of the following most accurately describes the vagus nerve?
- A.
"fight or flight"
- B.
Norepinephrine
- C.
Parasympathetic
- D.
Causes tachycardia
Correct Answer
C. ParasympatheticExplanation
The vagus nerve is a part of the parasympathetic nervous system. It is responsible for regulating various bodily functions such as heart rate, digestion, and breathing. Unlike the "fight or flight" response associated with the sympathetic nervous system, the vagus nerve promotes a calming and relaxing effect on the body. Therefore, the answer "parasympathetic" accurately describes the vagus nerve's role in the body.Rate this question:
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- 24.
What is the term for the sequence of events that occur during one heartbeat?
- A.
Stroke volume
- B.
Cardiac output
- C.
Cardiac cycle
- D.
Systole
Correct Answer
C. Cardiac cycleExplanation
The term for the sequence of events that occur during one heartbeat is called the cardiac cycle. This includes the contraction and relaxation of the heart chambers, as well as the opening and closing of the heart valves. The cardiac cycle is responsible for pumping blood throughout the body and ensuring proper circulation.Rate this question:
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- 25.
Which of the following contains 70ml?
- A.
The cardiac output
- B.
The volume of a ventricle
- C.
An average stroke volume
- D.
The amount of blood that flows through the pulmonary capillaries in one minute
Correct Answer
C. An average stroke volumeExplanation
An average stroke volume refers to the amount of blood pumped out of the heart by a ventricle with each contraction. Therefore, it makes sense that an average stroke volume would contain a specific volume of blood, in this case, 70ml.Rate this question:
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- 26.
Which of the following refers to a positive inotropic effect?
- A.
Heart block
- B.
A slow heart rate
- C.
A rapid heartbeat
- D.
An increased myocardial contractile force
Correct Answer
D. An increased myocardial contractile forceExplanation
An increased myocardial contractile force refers to a positive inotropic effect. Inotropic effect refers to the ability of the heart to contract and pump blood effectively. When there is an increased myocardial contractile force, the heart muscle contracts with more force, leading to a stronger and more efficient pumping action. This can result in an increased cardiac output and improved circulation.Rate this question:
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- 27.
Sympathetic stimulation to the heart
- A.
Decreases stroke volume
- B.
Increases heart rate
- C.
Causes bradycardia
- D.
Decreases cardiac output
Correct Answer
B. Increases heart rateExplanation
Sympathetic stimulation to the heart increases heart rate because the sympathetic nervous system releases norepinephrine, which binds to beta-adrenergic receptors in the heart. This binding activates a signaling pathway that leads to an increase in the rate of depolarization in the sinoatrial (SA) node, the natural pacemaker of the heart. This increased depolarization rate results in a faster heart rate.Rate this question:
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- 28.
Cardiac output is determined by heart rate and
- A.
Systemic vascular resistance
- B.
Stroke volume
- C.
Hematocrit
- D.
Hemoglobin concentration
Correct Answer
B. Stroke volumeExplanation
Cardiac output refers to the amount of blood pumped by the heart per minute, and it is determined by two factors: heart rate and stroke volume. Heart rate is the number of times the heart beats per minute, while stroke volume is the amount of blood ejected from the heart with each contraction. Therefore, the correct answer is stroke volume, as it directly affects the cardiac output by determining the amount of blood pumped out of the heart with each beat.Rate this question:
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- 29.
What is the term that refers to an increase in stroke volume in response to the stretching of the heart?
- A.
Starling's law of the heart
- B.
A positive inotropic effect
- C.
Heart block
- D.
Angina pectoris
Correct Answer
A. Starling's law of the heartExplanation
Starling's law of the heart refers to the increase in stroke volume that occurs when the heart muscle is stretched. This law states that the more the heart muscle is stretched, the stronger the force of contraction and the greater the volume of blood pumped out of the heart. This mechanism allows the heart to adapt and respond to changes in venous return and maintain an adequate cardiac output.Rate this question:
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- 30.
Atropine is a muscarinic antagonist and is therefore used to
- A.
Relieve bradycardia
- B.
Decreased heart rate
- C.
Block the effects of norepinephrine
- D.
Increase myocardial contractile force
Correct Answer
A. Relieve bradycardiaExplanation
Atropine is a muscarinic antagonist, which means it blocks the action of acetylcholine at muscarinic receptors. Acetylcholine normally slows down the heart rate by stimulating these receptors, so by blocking them, atropine can relieve bradycardia, which is a decreased heart rate. This allows the heart to beat at a more normal rate.Rate this question:
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- 31.
Which of the following is descriptive of a drug that causes a (+) inotropic effect, a (+) dromotropic effect, and a (+) chronotropic effect?
- A.
Vagomimetic
- B.
Sympathomimetic
- C.
Antimuscarinic
- D.
Parasympatholytic
Correct Answer
B. SympathomimeticExplanation
A drug that causes a (+) inotropic effect increases the force of contraction of the heart muscle. A drug that causes a (+) dromotropic effect increases the conduction of electrical impulses through the heart. A drug that causes a (+) chronotropic effect increases the heart rate. Sympathomimetic drugs mimic the effects of the sympathetic nervous system, which is responsible for the "fight or flight" response. These drugs stimulate the release of adrenaline and noradrenaline, leading to increased heart rate, force of contraction, and conduction of electrical impulses. Therefore, sympathomimetic is the correct answer.Rate this question:
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- 32.
Which of the following drugs is sympathomimetic?
- A.
Beta1 adrenergic blocker
- B.
Muscarinic agonist
- C.
Vagolytic
- D.
Beta1 adrenergic agonist
Correct Answer
D. Beta1 adrenergic agonistExplanation
A sympathomimetic drug is a drug that mimics the effects of the sympathetic nervous system, which is responsible for the "fight or flight" response. Beta1 adrenergic agonists specifically stimulate beta1 adrenergic receptors, which are found in the heart and increase heart rate and contractility. Therefore, a beta1 adrenergic agonist is considered sympathomimetic as it mimics the effects of the sympathetic nervous system.Rate this question:
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- 33.
An increased afterload (e.g., hypertension)
- A.
Is usually caused by arteriolar dilation
- B.
Increases the work of the heart
- C.
Can only occur when preload increases
- D.
Is usually caused by intense parasympathetic (vagal) discharge
Correct Answer
B. Increases the work of the heartExplanation
An increased afterload refers to the increased resistance that the heart has to pump against, typically caused by conditions like hypertension. This increased resistance puts more workload on the heart, as it has to generate higher pressure to overcome the increased afterload and maintain adequate blood flow. Therefore, an increased afterload increases the work of the heart.Rate this question:
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- 34.
An increased preload
- A.
Decreases cardiac output
- B.
Increases stroke volume
- C.
Increases cardiac reserve
- D.
Increases afterload
Correct Answer
B. Increases stroke volumeExplanation
An increased preload refers to the increased volume of blood that fills the ventricles of the heart during diastole. This increased volume stretches the myocardial fibers, leading to a more forceful contraction during systole. As a result, the stroke volume, which is the amount of blood pumped out of the heart with each contraction, increases. Therefore, the correct answer is that an increased preload increases stroke volume.Rate this question:
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- 35.
Cardiac output
- A.
Is determined by heart rate and pulse
- B.
Decreases in response to sympathetic nerve stimulation
- C.
Increases in response to vagal discharge
- D.
Is determined by heart rate and stroke volume
Correct Answer
D. Is determined by heart rate and stroke volumeExplanation
Cardiac output refers to the amount of blood pumped by the heart per minute. It is determined by two factors: heart rate, which is the number of times the heart beats per minute, and stroke volume, which is the amount of blood pumped by the heart with each beat. An increase in heart rate or stroke volume leads to an increase in cardiac output, while a decrease in either of these factors results in a decrease in cardiac output. Therefore, the correct answer states that cardiac output is determined by both heart rate and stroke volume.Rate this question:
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- 36.
Increased return of the blood to the heart stretches the muscle, thereby
- A.
Stimulating the sympathetic nerve
- B.
Activating the beta1 adenergic receptors
- C.
Closing the AV valves
- D.
Increasing stroke volume
Correct Answer
D. Increasing stroke volumeExplanation
When the return of blood to the heart increases, it stretches the muscle of the heart. This stretching stimulates the sympathetic nerve, which activates the beta1 adrenergic receptors. This activation leads to the closing of the AV valves and ultimately increases the stroke volume. The stroke volume refers to the amount of blood pumped out of the heart with each contraction. Therefore, the correct answer is that increased return of blood to the heart increases the stroke volume.Rate this question:
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- 37.
An ejection fraction of 30% is
- A.
Normal
- B.
Characteristic of a healthy person who is engaged in aerobic exercise
- C.
Characteristic of a failing heart
- D.
The amount of oxygenated hemoglobin in the blood on the left ventricle
Correct Answer
C. Characteristic of a failing heartExplanation
An ejection fraction of 30% refers to the percentage of blood that is pumped out of the left ventricle with each heartbeat. A normal ejection fraction is typically between 50-70%. Therefore, an ejection fraction of 30% is characteristic of a failing heart, as it indicates that the heart is not effectively pumping blood out to the body.Rate this question:
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- 38.
A stenotic aortic valve
- A.
Causes right ventricular hypertrophy and right-sided heart failure
- B.
Increases afterload, thereby increasing the work of the left ventricle
- C.
Causes a right-to-left shunt
- D.
Is a narrowing of the semilunar valve
Correct Answer
B. Increases afterload, thereby increasing the work of the left ventricleExplanation
A stenotic aortic valve causes narrowing of the valve, which obstructs the flow of blood from the left ventricle to the aorta. This obstruction increases the pressure that the left ventricle needs to generate in order to pump blood out of the heart. This increased pressure, known as afterload, leads to an increase in the workload of the left ventricle as it has to work harder to overcome the obstruction and pump blood effectively. Therefore, the correct answer is that a stenotic aortic valve increases afterload, thereby increasing the work of the left ventricle.Rate this question:
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- 39.
Which of the following is the most likely consequence of acute left ventricular failure?
- A.
Jugular vein distention
- B.
Hepatomegaly and splenomegaly
- C.
Pulmonary edema
- D.
Pedal edema
Correct Answer
C. Pulmonary edemaExplanation
Acute left ventricular failure can lead to pulmonary edema, which is the accumulation of fluid in the lungs. When the left ventricle fails to pump blood effectively, it causes an increase in pressure in the pulmonary circulation. This increased pressure results in fluid leaking from the blood vessels into the alveoli of the lungs, leading to pulmonary edema. Symptoms of pulmonary edema include shortness of breath, coughing, wheezing, and pink frothy sputum.Rate this question:
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- 40.
Most of the symptoms of acute left-sided heart failure are
- A.
Relieved by morphine
- B.
Cured by an antibiotic
- C.
Respiratory in nature (e.g., dyspnea, orthopnea)
- D.
Confined to the lower extremities
Correct Answer
C. Respiratory in nature (e.g., dyspnea, orthopnea)Explanation
Acute left-sided heart failure is characterized by the inability of the left side of the heart to pump blood effectively, leading to a backup of fluid into the lungs. This fluid accumulation in the lungs can cause respiratory symptoms such as dyspnea (shortness of breath) and orthopnea (difficulty breathing while lying flat). Morphine is a medication that can help relieve these respiratory symptoms by reducing anxiety and relaxing the respiratory muscles. Antibiotics are not effective in treating acute left-sided heart failure as it is not caused by an infection. The symptoms of acute left-sided heart failure are not confined to the lower extremities, but rather primarily affect the respiratory system.Rate this question:
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- 41.
Which of the following is an example of forward failure?
- A.
Blood accumulates in the pulmonary capillaries, elevating pressure and causing pulmonary edema
- B.
Diminished renal blood flow stimulates the kidney to decrease urinary output and to retain Na+ and water
- C.
Blood distends the jugular vein
- D.
Blood distends the liver, causing hepatomegaly and digestive symptoms
Correct Answer
B. Diminished renal blood flow stimulates the kidney to decrease urinary output and to retain Na+ and waterExplanation
Forward failure refers to the inability of the heart to pump blood effectively, leading to a backup of blood in the circulatory system. In this case, diminished renal blood flow stimulates the kidney to decrease urinary output and retain sodium (Na+) and water. This is an example of forward failure because the decreased renal blood flow is causing a decrease in the excretion of urine and an increase in fluid retention, contributing to the backup of blood in the circulatory system.Rate this question:
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- 42.
Furosemide (Lasix), a potent diuretic, is administered in acute ventricular failure in order to
- A.
Strengthen myocardial contractile force
- B.
Increase plasma k+
- C.
Excrete excess water and relieve the edema
- D.
Relieve pain
Correct Answer
C. Excrete excess water and relieve the edemaExplanation
Furosemide (Lasix) is a potent diuretic that is administered in acute ventricular failure to excrete excess water and relieve the edema. Diuretics like furosemide work by increasing the excretion of water and electrolytes, such as sodium and chloride, from the body through increased urine production. This helps to reduce the fluid overload and edema commonly seen in ventricular failure. Strengthening myocardial contractile force, increasing plasma K+, and relieving pain are not the primary mechanisms of action for furosemide in this context.Rate this question:
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- 43.
Digoxin, a drug used in the treatment of heart failure, increases contractile force and is therefore called a
- A.
Diuretic
- B.
(+) dromotropic agent
- C.
(+) inotropic agent
- D.
(+) chronotropic agent
Correct Answer
C. (+) inotropic agentExplanation
Digoxin is a medication that is commonly used in the treatment of heart failure. It works by increasing the contractile force of the heart, which means it strengthens the heart's ability to pump blood. This makes it an inotropic agent. It does not have any diuretic effect, does not affect the conduction of electrical impulses in the heart (dromotropic effect), or have any effect on heart rate (chronotropic effect).Rate this question:
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- 44.
An increase in venous return causes an increase in cardiac output. This is accomplished by
- A.
A (+) inotropic effect
- B.
Depolarization
- C.
Starling's law of the heart
- D.
A (+) chronotropic effect
Correct Answer
C. Starling's law of the heartExplanation
An increase in venous return causes an increase in cardiac output due to Starling's law of the heart. According to this law, the more the cardiac muscle fibers are stretched during diastole, the greater the force of contraction during systole. When venous return increases, it leads to an increase in preload, which stretches the cardiac muscle fibers. This increased stretch results in a stronger contraction during systole, leading to an increase in cardiac output.Rate this question:
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- 45.
Milliliters/beat x beats/minute defines
- A.
Stroke volume
- B.
Ejection fraction
- C.
Cardiac reserve
- D.
Cardiac output
Correct Answer
D. Cardiac outputExplanation
Milliliters/beat x beats/minute defines cardiac output. Cardiac output is the volume of blood pumped by the heart per minute and is calculated by multiplying the stroke volume (the amount of blood pumped per heartbeat) by the heart rate (number of beats per minute). This measurement is important in assessing the overall performance of the heart and determining its ability to meet the body's oxygen and nutrient demands.Rate this question:
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- 46.
Which of the following is the blood vessel that distributes blood to organs?
- A.
Arteries
- B.
Capillaries
- C.
Venules
- D.
Arterioles
- E.
Veins
Correct Answer
A. ArteriesExplanation
Arteries are the blood vessels that distribute blood to organs. They carry oxygen-rich blood away from the heart and deliver it to various parts of the body. Arteries have thick, elastic walls that help them withstand the high pressure of blood flow. This allows them to efficiently transport blood to organs and tissues throughout the body.Rate this question:
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- 47.
This is a blood vessel that conveys blood from the tissues back to the heart.
- A.
Artery
- B.
Arteriole
- C.
Aorta
- D.
Vein
- E.
Capillary
Correct Answer
D. VeinExplanation
A vein is a blood vessel that carries blood from the tissues back to the heart. Unlike arteries, veins have thinner walls and contain valves that help prevent the backflow of blood. Veins also have a larger diameter and are often located closer to the surface of the skin, making them more visible.Rate this question:
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- 48.
Which artery wall is responsible for vasoconstriction?
- A.
Tunica interna
- B.
Tunica media
- C.
Tunica externa
- D.
Tunica albuginea
- E.
Tunica fascia
Correct Answer
B. Tunica mediaExplanation
The tunica media is responsible for vasoconstriction. It is the middle layer of the artery wall and contains smooth muscle cells that can contract and narrow the diameter of the artery, reducing blood flow.Rate this question:
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- 49.
This layer of the artery is composed mainly of elastic and collagen fibers.
- A.
Tunica interna
- B.
Tunica media
- C.
Tunica externa
- D.
Tunica albuginea
- E.
Tunica fascia
Correct Answer
C. Tunica externaExplanation
The tunica externa is the correct answer because it is the outermost layer of an artery and is primarily made up of elastic and collagen fibers. This layer provides support and protection to the artery, helping it maintain its shape and structure.Rate this question:
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- 50.
When an artery or arteriole is damaged, its smooth muscle contracts producing
- A.
A tear in the artery
- B.
A branch off the artery called an arteriole
- C.
A vascular spasm
- D.
Tetanus
- E.
Constriction of the outer four layers
Correct Answer
C. A vascular spasmExplanation
When an artery or arteriole is damaged, the smooth muscle in the vessel wall contracts, causing a vascular spasm. This contraction helps to reduce blood flow to the damaged area and prevent further bleeding. It is a protective mechanism that allows time for clotting factors to form a clot and begin the healing process.Rate this question:
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Current Version
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Mar 21, 2023Quiz Edited by
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Oct 29, 2015Quiz Created by
Kittykema
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