* Skin * Comprised of all 4 main tissue types * Epithelial * Connective * Muscular * Nervous * Part of the integumentary system * Function: * Protection * Body temperature regulation * Vitamin D synthesis * Sensation to touch, pressure, pain and temperature * 2 main regions: * epidermis * 5 strata * corneum * top layer, cornified layer, layers of dead cells and soft keratin * lucidum * granulosum * spinosum * basale * deepest layer, contain melanocytes * stores melanin which contributes to skin color * * * * dermis * dense irregular connective tissue * fibroblasts * adipose cells * macrophages * collagen * elastic reticular fibers * 2 layers: * papillary layer * small projections = papillae extend into epidermis = foot/hand prints * * reticular layer * (hypodermis basal layer) * joins these 2 layers to underlying muscles and bones * long loose connective tissue * most of body fat is found in this region * sweat gland (coiled) * found in the dermis * extend to the epidermis by means of a duct and pore * aid in excretion of wastes and help regulate body temperature * sebaceous (oil) glands * found in dermis * associates with hair follicles (usually attached and lumpy) * produce sebum * lipid-rich substance helps keep the hair follicle soft * lubricates and protects the skin and reduces moisture
* Skin * Comprised of all 4 main tissue types * Epithelial * Connective * Muscular * Nervous * Part of the integumentary system * Function: * Protection * Body temperature regulation * Vitamin D synthesis * Sensation to touch, pressure, pain and temperature * 2 main regions: * epidermis * 5 strata * corneum * top layer, cornified layer, layers of dead cells and soft keratin * lucidum * granulosum * spinosum * basale * deepest layer, contain melanocytes * stores melanin which contributes to skin color * * * * dermis * dense irregular connective tissue * fibroblasts * adipose cells * macrophages * collagen * elastic reticular fibers * 2 layers: * papillary layer * small projections = papillae extend into epidermis = foot/hand prints * * reticular layer * (hypodermis basal layer) * joins these 2 layers to underlying muscles and bones * long loose connective tissue * most of body fat is found in this region * sweat gland (coiled) * found in the dermis * extend to the epidermis by means of a duct and pore * aid in excretion of wastes and help regulate body temperature * sebaceous (oil) glands * found in dermis * associates with hair follicles (usually attached and lumpy) * produce sebum * lipid-rich substance helps keep the hair follicle soft * lubricates and protects the skin and reduces moisture