Compared with the walls of arteries, the walls of capillaries.
a. are thicker
b. are thinner
c. lack valves
d. have more resistance

Which of the following would be a body response when stepping outside without a coat on a snowy day? a. senaceous glands. secrete more senum b. more liquid is transported by the body to the skin fir insulation c. blood vessels in the skin narrow and contract d. blood vessels in the skin expand