Biology
Assertion (A): Vasoconstriction is the phenomenon in which the blood vessels become wider and supply more amount of blood to the skin.
Reason (R): Vasoconstriction normally occurs during cold climatic conditions or when a person becomes nervous.
- A is True and R is False.
- A is False and R is True.
- Both A and R are True.
- Both A and R are False.
Skin
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Answer
A is False and R is True.
Reason — Vasoconstriction is the narrowing of blood vessels, not widening. It reduces blood flow to the skin, helping to conserve body heat during cold conditions or stress. In cold weather, vasoconstriction helps reduce heat loss. It also occurs during nervousness or fear, redirecting blood flow to vital organs.
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