Human body temperature is kept within a narrow range. When the core body temperature is too low, this is detected by the thermoregulatory centre in the brain. Describe how the body responds when a decrease in core body temperature is detected.
Human body temperature is maintained at around 37oC through homeostasis. This monitors the core body temperature through thermoreceptors in hypothalamus and leads to a response if the temperature goes above or below 37 oC.If body temperature decreases this leads to the rapid contraction of muscle, known as shivering, the purpose of this is to produce heat through respiration of glucose within the muscle, in order to increase body temperature. Secondly, blood vessels (arteries) supplying the skin decrease their diameter, called vasoconstriction. This causes less blood flow to capillaries in the skin, meaning less heat loss to the surroundings.Common misconceptions with this question include: Blood vessels move (blood vessels stay in the same place, they constrict or dilate in order to change the volume of blood moving through them), capillaries or veins constrict (arteries, the blood vessels leading to capillaries, constrict not the capillaries themselves or the veins which leave the capillaries) and explanation of hair erection and trapping of air (this question specifically relates to human body response, this mechanism only occurs in animals with a thick fur coat).
