Select the correct option regarding the following two statements labelled Assertion (A) and Reason (R). Assertion (A): Blood pressure increases temporarily during exercise. Reason (R): Exercise increases heart rate and the volume of blood pumped by the heart per minute.
Both A and R are true, and R is the correct explanation of A
During exercise the body needs more oxygen and nutrients, so the heart rate rises and the volume of blood pumped per minute (cardiac output) increases. Because cardiac output = heart rate × stroke volume, a rise in either factor raises the blood pressure temporarily. So Assertion (A) is true.
The Reason (R) states exactly this mechanism – higher heart rate and higher volume of blood pumped per minute – and this is precisely the physiological cause of the temporary rise in blood pressure described in the assertion. So R is true and it correctly explains A.
Hence, the answer is Both A and R are true, and R is the correct explanation of A.
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Protein factory in human cell is
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