A person in hot weather is unable to maintain body temperature. Which physiological process has failed?
- A. Vasodilation & sweating
- B. Vasoconstriction
- C. Shivering
- D. Renin secretion
Explanation
Cooling in hot conditions depends on dilating the skin arterioles so more warm blood reaches the surface and on evaporating sweat, which draws latent heat from the skin. Vasoconstriction and shivering are the responses to cold, so their failure would show in the opposite conditions. Renin controls blood pressure and sodium balance rather than temperature.