What are the functions of the skin?

Derivatives of the Skin

Sweat Glands
• ~3 million of them throughout the body!
• Per person!

Eccrine Sweat Glands
• Releases into skin surface
• Most abundant sweat glands
• Also on soles, palms, and forehead
• Secretory part in dermis

What makes you sweat

Apocrine Sweat Glands
• Empty into hair follicles
• Larger then eccrine
• Axillary and anogenital areas
• Fatty and protein substances
• Milky and Yellowish color… oooo!
• Released during pain, stress, and sex?

Ceruminous Glands
• Release earwax!

Mammary Glands
• Secrete milk!
• We’ll talk about them a little bit later

Sebaceous Glands
• Oil glands – all over body
• Produce sebum
• Release into hair follicle
– Maybe a pore
• Hormones stimulate

Hair and Hair Follicles
• What is the point?
• Some people get a lot… lucky!

Some people don’t get any 

Hair
• Growths of the epidermis variously distributed over the body.
• Dead keratinized cells
• DIVIDED INTO TWO MAJOR DIVISIONS:
• 1. THE ROOT
• 2. THE SHAFT

THE ROOT
• Portion just below the surface that penetrates into the dermis.
• Surrounding the root is a hair follicle
• At the base of each follicle is an enlarged structure called a bulb.

Hair Follicle
• Each follicle gets
– Arrector pilli – smooth muscle
– Nerves! – root hair plexus
– Hair papilla – capillaries!

NAILS
• Hard keratinized cells of the epidermis
• 3 parts:
• 1. Nail body- portion that is visible
• 2. Free edge-Any part that may project beyond the distal end of the digit.
• 3. Nail root-Hidden in proximal nail groove

Structure of a hair follice

Hair Growth