Biology

Cardiovascular and Nervous System

981 Questions

Review the human cardiovascular system through these competitive exam practice questions. Key areas include heart valves, cardiac impulse pathways, and blood pressure regulation. A solid grasp of these fundamentals is crucial for science sections.

Heart anatomy and valvesCardiac impulse conductionBlood pressure mechanicsHeartbeat regulation

Cardiovascular and Nervous System Questions

Multiple choice

Which of the following does not characterise a mammalian heart?

  1. In a human heart, a single heartbeat lasts for about 0.8 seconds.

  2. The impulses are delayed for about 0.1 s at the bundle of his.

  3. The SA node generates electrical impulses.

  4. Few cardiac cells can contract without any signal from the brain.

  5. The heart is energetically a syncytium.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is incorrect as the atrioventricular node is located in the wall between the right atrium and the right ventricle. 

Multiple choice

Bicuspid valve is located between

  1. right atrium and pulmonary artery

  2. posterior aorta and atrium

  3. left atrium and left ventricle

  4. right atrium and right ventricle
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Bicuspid valve is present between left atrium and left ventricle. It has two flaps. It guards the opening between left atrium and left ventricle.

Multiple choice

Which among the following statements regarding heart sounds is incorrect?

  1. Heart sounds are a result of a beating heart and resultant blood flow.

  2. Heart murmurs are pathological noises that results from abnormal blood flow in the heart or blood vessels.

  3. Turbulent blood flow is a result of stenotic (narrowed) valves or blood vessels.

  4. Third heart sound is pathological in children but physiological in adults.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Third heart sound is physiological in children, but pathological in adults. The four heart sounds are a result of the atrial systole and vibration of the AV valves, due to blood rush during atrial systole.

Multiple choice

After complete check up, the doctor told Mr. Khare that his wife is suffering from a pathological situation of the heart, arising from ectopic focus. Which among the following diseases is this?

  1. Extrasystole

  2. Endocarditis

  3. Cardiac tamponade

  4. Aortic valve stenosis

  5. Mitral stenosis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Extrasystole is a pathological situation due to abnormal impulses arising from ectopic focus. It is expressed as an abnormal systole that occurs during the early diastole. Extrasystole is due to a rising of excitability above the normal, which usually occurs after the end of the relative refractory period.

Multiple choice

Which among the following cardiovascular defects is accompanied by action potentials of extended duration and flattened oscillations of intracellular calcium ions?

  1. Diastolic dysfunction

  2. Arrhythmogenic right ventricular cardiomyopathy

  3. Dilative cardiomyopathy

  4. Restrictive cardiomyopathy

  5. Hypertrophic cardiomyopathy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Dysfunction is accompanied by action potentials of extended duration and flattened oscillations of intracellular Ca2+. During systole, the spike in cytosolic Ca2+ concentration is muted, capping power, while during diastole, it takes too long to pump the Ca2+ back into the sarcoplasmic reticulum, interfering with proper relaxation.

Multiple choice

Action potentials (electrical impulses) in the heart originate in specialized cardiac muscle cells, called autorhythmic cells. Which among the following statements is incorrect regarding the action potentials and the autorhythmic cells?

  1. The cardiac cycle spreads along both atria through the gap junctions of the cardiac muscle fibers.

  2. At the atrioventricular node slight delay of the electrical transmission occurs.

  3. The bundle of His receives the action potential from the AV node.

  4. The autorhythmic cells serve as a pacemaker to initiate the cardiac cycle.

  5. The bundle of His conducts the action potential from the interventricular septum, down to the apex of the heart.
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

The Purkinje fibers are large‐diameter fibers that conduct the action potential from the interventricular septum, down to the apex, and then upward through the ventricles.

Multiple choice

A ventricle is a muscular chamber that pumps blood out of the heart and into the circulatory system. Which among the following statements regarding the ventricles of heart is false?

  1. When the left ventricle contracts, the left AV valve gets closed.

  2. When the left ventricle relaxes, the aortic semilunar valve gets closed.

  3. The left ventricle is smaller and its walls are thinner than those of the right ventricle.

  4. The chordae tendineae are attached to papillary muscles at the opposite, bottom side of the right ventricle.

  5. When the right ventricle relaxes, there is more pressure in the pulmonary trunk.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The left ventricle is the pumping chamber for the systemic circulation. 

Multiple choice

Which among the following does not characterises a mammalian heart?

  1. The heart is effectively a syncytium.

  2. Few cardiac cells can contract without any signal from the nervous system.

  3. The SA node generates electrical impulses.

  4. The impulses are delayed for about 0.1s at bundle of His.

  5. This entire cycle, a single heart beat, lasts about 0.8 seconds.

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The atrioventricular node is located in the wall between the right atrium and the right ventricle. Here, the impulses are delayed for about 0.1s before spreading to the walls of the ventricle.

Multiple choice

In order to magnify the efficiency of contraction and cardiac output, the conduction system of a mammalian heart follows various mechanisms. Which of the following statements regarding the conduction system is incorrect?

  1. Depolarisation propagates through cardiac muscle very sluggishly.

  2. Temporary inactivation of certain ion channels helps heart in relaxation.

  3. The action potentials of cardiac muscle are unusually sustained.

  4. There is a substantial atrial to ventricular delay.

  5. There is a coordinated contraction of ventricular cells.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct Answer: Depolarisation propagates through cardiac muscle very sluggishly.

Multiple choice

Which among the following is a secondary form of pericarditis?

  1. Systemic sclerosis

  2. Dressler's syndrome

  3. Discoid lupus erythematosus

  4. Eczema

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Dressler's syndrome is a secondary form of pericarditis that occurs in the setting of injury to the heart or the pericardium .It consists of a triad of features, fever, pleuritic pain and pericardial effusion.

Multiple choice

The mammalian heart is a myogenic heart. What does this statement mean?

  1. The heart beats originate from a muscle, but it is regulated by nerves.

  2. The heart beats originate from a nerve, but it is regulated by muscles.

  3. The heart beats originate from a muscle, and is regulated by muscles.

  4. The heart beats originate from a nerve, and is regulated by nerves.

  5. The heart beats originate from the heart, and regulated by heart.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This answer is correct. The heart beats originate from a muscle, but it is regulated by nerves.