Questions & Answers

The resting person usually has a pulse rate between_____beats per minute.
(a)72 and 78
(b)72 and 80
(c)72 and 76
(d)70 and 80

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Hint: A resting heart rate is low because the heart pumps the lowest amount of blood as the body cells do not require much oxygen at this time. Active people often have a lower heart rate because their heart muscle is in better condition and doesn’t need to work as hard to maintain a steady beat.

Complete answer:
The resting person usually has a pulse rate between 70 (beats per minute) and 80 (beats per minute). A heart rate lower than 60 doesn’t necessarily mean a medical problem. It could be the result of taking a drug.

Additional Information: -A heart beats around 115,000 times each day.
- Our heart pumps about 2,000 gallons of blood every day.
-An electrical system that controls the rhythm of your heart is called the cardiac conduction system.
-The beating sound of the heart is caused by the valves of the heart opening and closing.
-The right side of the heart pumps blood into our lungs, the left side pumps oxygenated blood around the body.
-The Sinu-auricular node is called the pacemaker because it is first to originate a cardiac impulse.
-S.A. node has the highest degree of auto rhythmicity and least conductivity.
-The nerve fibres stimulate and increase the rate and depth of contraction of the S.A. node through a neurotransmitter chemical called adrenalin.
-Atrio-ventricular node is called the pace-setter it passes the impulse to the ‘bundles of his’ part of the heart.
So, the correct answer is, ’70 and 80.’

Note: The cardiac inhibitory centre associated with parasympathetic (inhibiting the organ from overworking) nerve fibre inhibits the rate of the heartbeat to about 20-30 times per minute through a chemical called acetylcholine.