Watching this resources will notify you when proposed changes or new versions are created so you can keep track of improvements that have been made.
Favoriting this resource allows you to save it in the “My Resources” tab of your account. There, you can easily access this resource later when you’re ready to customize it or assign it to your students.
The skin contains a network of small blood vessels containing muscle fibers in their tunica media. These muscles are under the control of the sympathetic nervous system and provide an efficient means of thermo-regulation through vasoconstriction and vasodilation.
When vasoconstricted blood flow through the skin is reduced and so less core heat is lost. With restricted blood flow the skin appears paler. When vasodilated blood flow through the skin is increased meaning more core heat can be lost through radiation. With increased blood flow the skin appears red.
Arteriovenous anastomoses can be found in areas of the body exposed to maximal cooling, such as the hands, feet, nose, lips and ears. These areas are called apical structures and are richly innervated. The anastomoses connect cutaneousarterioles and venules directly, playing an important role in the reduction of blood flow in a cold environment.
Source: Boundless. “Blood Flow in the Skin.” Boundless Anatomy and Physiology. Boundless, 22 Aug. 2016. Retrieved 26 Sep. 2016 from https://www.boundless.com/physiology/textbooks/boundless-anatomy-and-physiology-textbook/cardiovascular-system-blood-vessels-19/blood-flow-through-the-body-185/blood-flow-in-the-skin-923-2180/