When smooth muscles in the walls of dermal blood vessels contract,
A) the vessels' lumen enlarge.
B) more blood enters the dermis.
C) blood is forced to the epidermis.
D) body heat is conserved.
E) more heat is lost.

Question

Quizplus · Accepted Answer

When smooth muscles in the walls of dermal blood vessels contract, the lumen of the vessels narrows, reducing blood flow to the skin's surface, which helps conserve body heat.

When Smooth Muscles in the Walls of Dermal Blood Vessels