The diagram below illustrates the physiological changes in the skin of an endotherm in two different environments: State 1 (cold environment) and State 2 (hot environment).
Which row in the table below correctly describes the coordination by the hypothalamus and the corresponding state of the skin's microvasculature and erector pili muscles when the organism transitions from State 2 to State 1?
• Hypothalamic center activated: Heat-loss center
• Arterioles: Dilate
• Shunt vessels: Constrict
• Erector pili muscles: Relax
• Hypothalamic center activated: Heat-gain center
• Arterioles: Constrict
• Shunt vessels: Dilate
• Erector pili muscles: Contract
• Hypothalamic center activated: Heat-gain center
• Arterioles: Dilate
• Shunt vessels: Constrict
• Erector pili muscles: Contract
• Hypothalamic center activated: Heat-loss center
• Arterioles: Constrict
• Shunt vessels: Dilate
• Erector pili muscles: Relax
