BIOL 1410 Lecture Notes - Lecture 19: Stratified Squamous Epithelium, Stratum Corneum, Melanin

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1410
• Professor: Diana Mlinar

Document Summary

Topic vix: integumentary system: integumentary system: overview. 2 layers : epidermis upper layer, dermis lower layer. Separated into 4-5 strata (sub-layers) based on cell types: o stratum basale . Migrate to surface as new cells produced in basale : melanocytes (10%) Produce pigment (melanin) for uv light protection . O e. g. sunburns, wrinkles (collagen damage), cancer (dna damage). O we all have the same relative number of melanocytes, but cells produce different amounts/shades of melanin. O albinos = no melanin lomoar cpsd| 987298. O blood (hemoglobin) - in dermis can give a pinkish tinge to fair skinned people. O stratum lucidum flat, dead cells (too far from blood supply) . 20 - 30 layers of flat dead cells filled with keratin (tough protein), surrounded by waterproofing glycolipid (prevents water loss) . Shed and replaced from below : dermis. Contains blood vessels, nerves, glands, hair follicles . Has projection into epidermis = dermal papillae .