Integumentary system

Skin

•Also known as Cutaneous membrane or Integument

•Adult:

•Area: 2 square meters (22 square feet)

•Wt: 4.5-5 kg (10-11 lbs)

•16% total body weight

•Thickness:

•Eyelids- 0.5mm (0.02 in)

•Heels- 4mm (0.16 in)

Most of the body- 1-2mm (0.04-0.08 in

TYPES:

   Epidermis

Epithelial tissue                            

   Dermis

Connective tisue   Hypodermis/ Subcutaneous tissue           

Fats, blood vessels

Epidermis

•4 principal types of cells: 

•Keratinocytes (90%), melanocytes (8%), Langerhans cells, and Merkel cells

•5 layers:

•Stratum corneum

•Stratum lucidum

•Stratum granulosa

•Start to degenerate

•Keratohyalin

•Lamellar granules

•Stratum spinosum

•Stratum basale/ stratum germinativum