. The regulation of temperature is done by the skin.

. The regulation of temperature is done by the skin.

 When the body is exercising vigorously or when the surrounding is hot:

Thermoreceptors in the skin detect an increase in environmental
temperature or heat sensors in the hypothalamus detect a rise in
the temperature of the blood.
1)
2) The sweat glands increase the production of sweat.
Vasodilation, increases the internal diameter of blood vessels so
that more blood is brought to the capillaries.
3)
4) Body loses heat as sweat evaporates.
Body loses heat as more blood is brought to the skin surface,
leading to increased heat loss by conduction, convection and
radiation.
5)
Metabolic rate is lowered leading to the decreased heat
production by cells.
6)
7) Body temperature is lowered.

When the body is at rest or when the surrounding is cold:

Thermoreceptors in the skin detect decrease in the environmental
temperature or heat sensors in the hypothalamus detect drop in
temperature of blood.
1)
2) The sweat glands stop production of sweat.
Vasoconstriction, reduces the internal diameter of blood vessels so
that less blood is brought to the capillaries.
3)
Body gains heat as erector muscles in the skin contract causing the
hairs to stand up, creating a layer of air which will act as insulation.
4)
Skeletal muscles contract and relax repeatedly; this shivering
resulting in production of heat.
5)
Less blood is brought to the skin surface so that less heat will be
lost.
6)
Metabolic rate is raised leading to increased heat production by
cells.
7)

8) Body temperature is raised.