BIOL 030 Lecture Notes - Lecture 4: Dermis, Fascia, Bending

• School: College of The Sequoias
• Department: Biology (BIOL)
• Course: BIOL 030
• Professor: Moore

Document Summary

Richly supplied with blood vessels and nerves. Includes dermal papillae: reticular layer, deeper layer-80% of thickness of dermis. Deep to the skin: also called superficial fascia. Three pigments contribute to skin color: melanin, most important pigment. Made from tyrosine: carotene, yellowish pigment from carrots and tomatoes, hemoglobin, caucasian skin contains little melanin, allows crimson color of blood to show through; hemoglobin is a red pigment. Chiefs parts of a hair: root imbedded in the skin, shaft projects above skins surface. Wall of hair follicle: ct root sheath, et root sheath. Arrector pili muscle: bundle of smooth muscle, hair stands erect when arrector pili contracts. Occur over entire body: except palms and soles. Secrete sebum an oily substance: most are associated with a hair follicle. Functions of sebum: collects dirt; softens and lubricates hair and skin. Sudoriferous glands: widely disturbed in body. Two types: eccrine gland, most numerous.