7.4 Arterioles and Sweat Flashcards
Where is sweat released?
On the skin via skin duct.
What does sweat do?
Evaporate heat energy taken from the skin
How are sweat glands stimulated?
By nerves from the hypothalamus.
Why is hair raised in cold temperatures?
Contractions of the erectors muscles.
What is the purpose of the hair standing up when it is cold?
Trap a layer of air that insulates the body.
How is energy lost on the skin besides sweat and hair erections?
Flowing through the surface of the capillaries by radiation.
What is the effect of muscles in the arterioles constricting?
Reducing blood supply to the surface of capillaries.
Where is blood diverted if it is not going to the capillaries?
The shunt vessel which dilates as blood flows through it.
What is the effect of the blood becoming diverted to the shunt?
Blood slows further from the skin surface so less energy is lost. This is called Vasoconstriction.
Where is the constriction of the arterioles and shuts controlled?
In the hypothalmus
When it is warm what do the shunt vessels do?
Shut vessels constrict and muscles in walls relax.
Blood flows trhough arterioles and the dilate
Blood flows close to surface.
When blood flows closer to the surface what is the effect of this?
More energy is lost. Vasodilation.
Methods of Energy Transfer
Radiation
Conduction
Convection
Evaporation
