Anatomy and Cell Biology 3309 Lecture Notes - Acinus, Glycoprotein, Eponychium

• School: Western University
• Department: Anatomy and Cell Biology
• Course: Anatomy and Cell Biology 3309
• Professor: Ron Podesta

Document Summary

Skin appendages: hair follicles and hair/nails, sebaceous glands and sebum, eccrine sweat glands and sweat, apocrine sweat glands serous secretions. Structure: bulb at base, dermal papilla vascularized, outside of hair: down growth of epithelium called external root sheath. Contains keratinocytes which form soft keratin: the hair itself, which is divided into three layers. Hair is composed of hard keratin: the outer cuticle, the middle cortex, the central medulla (may not be present in fine hairs) Arrector pili muscle associated with hair follicle. Develop as a growth off the side of the hair follicle. Basal cells renew, and cells fill up with lipid secretion until the cell dies and all is secreted into the hair follicle. Well developed ser for production of lipids. No myoepithelial cells arrangement of arrector pili muscle can help expel contents. Duct opens into hair follicle above sebaceous gland. Secretory product not altered in duct i. e. no resorption occurs in apocrine ducts.