Assertion: When there is a fall in the blood pressure due to loss of blood volume, this is compensated by vasoconstriction of veins.
Reason: Veins hold the extra amount of blood which can be shifted to the arteries as required.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
(b) If both Assertion and Reason are correct, but Reason is not the correct explanation of Assertion.
(c) If Assertion is correct but Reason is incorrect.
(d) If both the Assertion and Reason are incorrect.
(a) If both Assertion and Reason are correct and Reason is the correct explanation of Assertion.
Explanation:
When the blood pressure of an individual decreases due to loss of blood volume, then vasoconstriction of veins occurs. This shifts the little amount of blood from veins to arteries.