What does the body do when it is too hot?
Increased rate of sweating
- The hypothalamus sends messages to the sweat glands resulting in increased sweat production.
- Heat energy from the body will convert the water in sweat to water vapour.
- This lowers the body temperature.
Vasodilation
- Blood vessels called A small branch of an artery that leads to a capillary. near the surface of the skin dilate (get wider) allowing more blood to the skin surface where more heat can be lost by radiation.
Relaxation of hair erector muscles
- This prevents heat being trapped in a layer of air next to the skin.
Images of hair erector muscles. In the first they are relaxed, in the second they are contracted.