thermoregulation
Thermoregulation is the process in which an organism maintains their internal body temperature, regardless of the outer environment's temperature. As a result, thermoregulation regulates the amount of heat contained within the body despite prolonged exposure to either high or low temperatures.
IN MAMMALS
Warm-blooded mammals usually utilize their hair and body fat in order to preserve heat against harsh conditions. However, the body is provided with the following materials to preserve and release heat accordingly: the skin, the arterioles, and the muscles.
The integumentary system assists in keeping a constant body temperature by reacting differently to hot and cold conditions. When it's too hot, the skin activates its sweat glands to lose excess body heat through evaporative cooling. Additionally, arterioles relax to allow increased blood flow through the artery, increasing heat loss through convection and conduction.
Conversely, in the case of colder conditions, muscles under the skin contract, lifting the hair follicles upright to act as an insulating layer to trap heat. Additionally, the brain sends messages to muscles throughout the body to shiver, producing heat within the organism and bringing the body back to stable conditions.
The latter examples have provided examples of negative feedback mechanisms. In the case that a virus or bacteria attacks the body, a fever, a positive feedback, may occur.
A fever occurs as a result of the body's mechanism to kill off the virus or bacteria causing harm within the body. However, fevers can cause damage if it reaches high temperatures. Once the fever has run its course and killed the pathogen, the body will return to its natural temperature.
IN cold-blooded animals
Cold-blooded animals take on the temperature of their environment. Reptiles will lie flat towards the direction of the sun to increase the surface area of their skin to increase their body temperature and their metabolism. If the reptile is too hot, it will lighten its skin color or dig into cool soil. An advantage of being a cold-blood animal is that it requires much less energy to survive. However, cold-blooded animals must get warm enough to participate in activites that involve defensive and offensive actions.
