When core temperature might fall:

-The hypothalamus sends electrical impulses along motor neurones (nerve cells) to some of the muscles and to the skin.

-Nerve impulses causes muscles to contract and relax rapidly = shivering,

-Cells respire, glucose is oxidised to release energy to make ATP.

-Some of the energy is lost as heat, shivering therefore generates heat in the
muscle.

-Heat is then transferred into the blood as it passes through the muscles and then carried to the bloodstream (rest of the body)

-Nerve impulses also affect the smooth muscle in the walls of arterioles that supply blood to capillaries near the skin surface.

-The muscle contracts, narrowing the lumen of the arterioles and shutting off blood supply to the surface capillaries (Vasoconstriction)

	Created by andychueh96 over 11 years ago

Homeostatis Coordinating cell activities

Chapter 1: Communication