BIO 3342 Lecture Notes - Lecture 35: Arrector Pili Muscle, Basal-Cell Carcinoma, Body Odor
Document Summary
Protection : cushions and insulates deeper body organs, protects from chemicals and invading microorganisms, prevents unnecessary water loss across body surface, protects from uv radiation. Body temperature regulation : capillary networks and sweat glands regulate loss of heat from the body. Excretion : urea, salts, and water lose through sweat. Production of vitamin d : epidermal cells use uv radiation to synthesize vitamin d. Sensory reception : using senses helps receptors stay aware of condition at the body surface. Hypodermis : underlies the skin: composed primarily of adipose tissue to store fat, insulate and protect against heat loss, and absorbs and deflects blows. Skin color : reflects amount of melanin/carotene in skin & level oxygen & hemoglobin in blood vessels. Nails : modification of the epidermis that covers the dorsal tip of fingers and toes. Sebaceous glands : alveolar glands that empty into hair follicles, secrete sebum which lubricates the skin and hair & slows water loss across the skin.
