Which mechanism helps the body return to normal temperature during hyperthermia?

The body employs active heat loss mechanisms to manage hyperthermia, and the activation of the heat loss center is a crucial response. When the body temperature rises above normal due to factors like excessive heat, physical exertion, or illness, it triggers the hypothalamus to activate mechanisms aimed at dissipating heat.

This center regulates several physiological responses that promote cooling, such as dilation of blood vessels (vasodilation) in the skin, increased sweating, and enhancements in respiratory heat loss. By increasing sweat production, the body can facilitate evaporative cooling, which effectively lowers body temperature. Additionally, increased blood flow to the skin allows heat to dissipate more efficiently into the environment.

The other options—vasoconstriction, increased metabolic rate, and decreased sweating—do not support the body’s efforts to cool down during hyperthermia. Instead, vasoconstriction would reduce blood flow to the skin, inhibiting heat loss. An increased metabolic rate would generate more heat, exacerbating the issue. Decreased sweating directly counters the cooling process, making it harder for the body to return to a normal temperature. Thus, the activation of the heat loss center is fundamental for maintaining thermal homeostasis during hyperthermia.