Assertion (A): The mixing of oxygenated and deoxygenated blood does not occur in mammalian heart.
Reason (R): Within the heart blood flows in one direction only.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.

Subtopic:  Human Heart: Double Circulation |
 50%
From NCERT
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Assertion (A): The enlargement of Q and R waves indicates heart attack.
Reason (R): If any deviation in normal ECG occurs, it indicates some abnormality.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  ECG & Coronary Artery Disease |
 62%
From NCERT
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Assertion (A): Foetal heart contains mixed blood.
Reason (R): In foetus, pure blood gets mixed with impure blood through the foramen ovale present in the interatrial septum.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Human Heart: Gross Anatomy |
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Assertion (A): SA-node is called pacemaker.
Reason (R): SA node generates least number of action potentials to initiate rhythmic contraction of heart.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Human Heart: Gross Anatomy | Rhythmic Excitation of Human Heart: Part 1 | Rhythmic Excitation of Human Heart: Part 2 |
 88%
From NCERT
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Assertion (A): The cardiac output of a normal human is greater than an athelete.
Reason (R): The stroke volume of a normal men is greater than an athelete.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Human Heart: Cardiac Cycle |
 89%
From NCERT
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Assertion (A): The neural signals through the sympathetic nerves increase the heart-beat, thereby decreasing the cardiac output.
Reason (R): Adrenalin secretion drastically decrease cardiac output.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Regulation of Cardiac Activity |
 84%
From NCERT
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Assertion (A): All vertebrate have hepatic portal system.
Reason (R) All animals have hepatic portal system.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Human Heart: Double Circulation |
 53%
From NCERT
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Assertion (A): In joint diastole, all the four chambers of heart are in relaxed state.
Reason (R): The atrio-ventricular valves are open and the semilunar valves are closed at this stage.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Human Heart: Cardiac Cycle |
 63%
From NCERT
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Assertion (A): A symptom of acute chest pain is called 'Angina pectroris'. 
Reason (R): In this condition heart do not pump blood effectively to meet body needs.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Atherosclerosis, Hypertension & Ventricular Fibrillation |  DISORDERS OF CIRCULATORY SYSTEM |
 59%
From NCERT
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Assertion (A): Lymph is called the 'middle man' of body.
Reason (R): Exchange of nutrients, gases and other materials between blood and the cells always occur through this fluid.
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
Subtopic:  Lymph |
 87%
From NCERT
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