- Each hair is composed of columns of dead, keratinized epidermal cells bonded together by extracellular proteins.
- Present on most skin surfaces except palms and soles.
- Function for protection, decreases heat loss, and touch sensation
Anatomy of a hairs:
Shaft projects from the skin
Root embedded in the skin
Hair follicle surround the root of the hair
Arrector pili muscle :
a smooth muscle that attaches to the base of a hair follicle, causing the hair to "stand up straight"