Do sweat glands remove water, salts, and urea from the bloodstream? Does hair help to regulate body temperature?
In cold weather,the hair erector muscles just below the surface of the skin contract and our hair follicles become erect.This traps a layer of air all around our body,thus decreasing the amount of heat lost by convection currents.
In warm weather erector muscles relax and hair follicles lay flat on the surface of the skin.Air can more easily flow around our body,thus increasing the amount of heat lost by convection currents.
Yes,we lose water,urea and salts when we sweat.