Chapter 36: Human skin (the integumentary system) Leaving Certificate Biology Higher Level

Human skin

Functions of the skin Protection – acts as a barrier preventing entry of pathogens Excretion – excretes water, salts and a very small amount of urea Temperature regulation – goose bumps, hairs stand on end and vasoconstriction occur when cold; sweat produced, vasodilation, hairs lie flat when hot Fat storage – adipose tissue just below the skin stores fat and acts as an insulator Sense organ – sense organs such as temperature and pain receptors send signals to the brain when stimulated Production of vitamin D – sunlight action on the fatty tissue within the skin causes the production of vitamin D, which is needed to absorb calcium from the diet