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

2. Human skin

3. 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