Biology
Cardiovascular and Nervous System
983 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
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epithelium
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endothelium
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epicardium
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pleura
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C
Correct answer
Explanation
The covering of the heart is called pericardium. It is divided into three layers. The outer one is called epicardium.
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Blood enters the heart.
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Blood enters the lungs.
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Blood leaves the ventricles.
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Blood leaves the heart.
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C
Correct answer
Explanation
During diastole, the flow of blood from both the atria to the respective ventricle occurs. Diastole means relaxation of the heart chamber.
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SA node
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AV node
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Vagus nerve
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Cardiac nerves
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A
Correct answer
Explanation
The SA node is also known as the sinu-atrial node and is the natural pacemaker of the heart. Initiation of the heartbeat occurs in the SA node.
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epicardium
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myocardium
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endocardium
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All of the above
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D
Correct answer
Explanation
The heart wall is made of pericardium which is divided into three layers - epicardium, myocardium and endocardium.
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Left auricle
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Right auricle
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Left ventricle
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Right ventricle
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C
Correct answer
Explanation
The walls of the left ventricle are about three times thicker than the right ventricle as it has to supply the blood more forcefully to the large diameter of aorta.
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stop
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beat rhythymically
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beat arhythmically
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shrink
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B
Correct answer
Explanation
The heart will go on beating for a short time after it has been entirely removed.
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myogenic
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neurogenic
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Both (1) and (2)
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None of these
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A
Correct answer
Explanation
In the human heart, contraction is initiated by a special modified heart muscle known as sinoatrial node. It is located in the right atrium.
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speeding it up
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slowing it down
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it has no effect at all
B
Correct answer
Explanation
Heroin is an opioid that acts as a central nervous system depressant, which typically slows down heart rate and respiration.
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To protect the heart from mechanical shocks
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To allow the assimilation of various nutrients in blood
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To prevent the backflow of blood
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To prevent the mixing of oxygenated and deoxygenated blood
D
Correct answer
Explanation
The heart has different chambers to prevent the oxygen-rich blood from mixing with the blood containing carbon dioxide. The carbon dioxide-rich blood has to reach the lungs for the removal of carbon dioxide, and the oxygenated blood from the lungs has to be brought back to the heart.
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pericardium
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septum
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vena cava
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aorta
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myocardium
B
Correct answer
Explanation
This is the correct option. The chambers of the heart are separated by a partition called septum.
A
Correct answer
Explanation
An electrocardiogram (ECG or EKG) records the electrical activity of the heart over a period of time. It is a standard tool used to diagnose various heart conditions.
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Mitral valve
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Tricuspid valve
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Aortic valve
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Noneof these
A
Correct answer
Explanation
The mitral valve, also called the bicuspid valve, separates the left atrium from the left ventricle. It prevents backflow of oxygenated blood into the atrium when the ventricle contracts. The tricuspid valve is on the right side, and the aortic valve separates the left ventricle from the aorta.
C
Correct answer
Explanation
A pacemaker is a small device placed in the chest or abdomen to help control abnormal heart rhythms.
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Abnormalities of blood flow in the carotid arteries causes problems in the subcortical structures.
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Abnormalities of blood flow in the vertebral arteries cause problems in the brainstem.
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Formation of a local thrombus is one of the commonest causes of blood flow problems in the brain.
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At the base of the brain lies the circle of Willis.
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The carotid arteries form the posterior circulation to the brain.
E
Correct answer
Explanation
The carotid arteries form the anterior circulation to the brain, whereas the vertebral arteries merge to become the basilar artery (so called vertebrobasilar system), which constitutes the posterior circulation.
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heart
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muscle
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brain
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respiration