During a long run in the summer, Jenna's respiratory and heart rate increase to supply oxygenated blood to the tissues. In the dermis of the skin, which of the following occurs to prevent Jenna from overheating?
1) Sweating increases to cool the body
2) Blood vessels constrict to reduce blood flow to the skin
3) Hair stands on end to trap heat
4) Respiration rate decreases to conserve energy