ANP 1106 Chapter Notes - Chapter 5: Stratum Lucidum, Stratum Corneum, Stratum Basale

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1106
• Professor: Jackie Carnegie

Document Summary

The integumentary system consists of the skin and its derivatives (hair, nails, sweat and oil glands). The skin is composed of 2 main layers. The epidermis: a thick layer of flat (squamous), keratinized stratified epithelia and the outermost layer. Thin skin has much thinner strata and is missing the stratum lucidum. http://sketchymedicine. com/2012/1. 20 to 30 cell layers deep, 3/4 of epidermal thickness, dead. Keratin and plasma membranes protect skin against abrasion and penetration, waterproof. Protects deeper cells from external environment and from water loss. 2-3 rows of clear, flat, dead keratinocytes. 4-6 cell layers where keratinocytes go through keratinization (cells flatten, organelles disintegrate, cells are too far from dermal capillaries and suffocate) Several layers thick of keratinocytes that are attached to each other by desmosomes, which holds skin together and toughens epidermis by holding keratinocytes so closely together. Dendritic cells and melanin granules are most abundant in this layer. Dermal papilla hold epidermis on the dermis.