The extremities are usually allowed to cool in homeotherms, while the body core temperature can be conserved by warming the blood returning ... their energy intake to thermoregulation.

Ways in which the body can increase temperature are: Vasoconstriction - blood vessels are restricted and blood flow to skin stops so less heat is lost. Hair erector muscles contract - hairs stand ...

The hypothalamus then sends nerve impulses to effectors to change the temperature of the body. Effectors include sweat glands, blood vessels and muscles around the body.