On a hot day, the blood vessels in the skin of a healthy person
Answer and explanation
Correct answer: B. dilate and more heat is lost from the body surface
- Step 1: Vasodilation brings more blood close to the skin where heat is lost to the surroundings.
Answer
dilate and more heat is lost from the body surface.
Why not the others: constrict and less heat is lost from the body surface: constriction occurs in cold conditions. dilate and more heat is generated in the muscles: vasodilation increases heat loss, not heat generation. remain unchanged while the hypothalamus is inactive: the hypothalamus controls the response to temperature.
Practise more Human systems: endocrine, nervous and reproduction.
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