In Biology homeostasis is controlled in the brain, but how does the brain know and maintain that 36.9 degrees celcius? Are chemicals used, nerves, enzymes?
The body temperature is controlled by the anterior hypothalamus (the preoptic area). It directly senses the temperature, as well as evaluates the thermoreceptor signals coming from the skin and other parts of the body (e.g. mucous membranes). Based on these signals it promotes either heat retention or heat loss (by means of vasodilation, sweating, shivering etc. according to what is needed).
