Ch. 5 Study Guide
6 functions of the integumentary system.
protection, body temp regulation, excretion, blood reservoir, metabolic functions and cutaneous function.
Protection of the integumentary system
chemical, physical, and biological barrier.
Body temperature regulation of the integumentary system
Dilation (cooling) and constriction (warming) of dermal vessels; increases sweat glands.
Cutaneous sensation of the integumentary system.
exoreceptors sense touch and pain
Metabolic functions of the integumentary system.
synthesis of vitamin D precursor molecule in dermal blood vessels.
Blood reservoir of the integumentary system.
skin blood vessels store up to 5% of the body's blood volume.
Excretion of the integumentary system.
limited amounts of nitrogenous wastes are eliminated from the body in sweat , along with water and excess salts.
outermost superficial layer; functions in protection.
Hypodermis (superficial fascia)
Epidermis is composed of...
keratinized stratified squamous epithilium, consisting of keratinocytes, melanocytes, Merkel cells, and Langerhans' cells.
Dermis is composed of...
flexible connective tissue, consisting of fibroblasts, macrophages, and occasionally mast and white blood cells.
Hypodermis is composed of...
adipose and areolar connective tissue.
Stratum Basale (Basal Layer)
Is the deepest epidermal layer firmly attached to the dermis, consists of a single row of youngest keratinocytes. Undergoes rapid division, hence alternate name stratum germinativum.
Stratum Spinosum (Prickly Layer)
Consists of melanin granules and Langerhans' cells; cells contain a weblike system of intermediate filaments attached to the desmosomes. (Epidermis)
Stratum Granulosum (Granular Layer)
Consists of keratohyaline and lamellated granules; 3 to 5 thin layers in which drastic changes in kertinocyte appearance occurs. (Epidermis)
Stratum Lucidum (Clear Layer)
Consists of a few rows of flat, dead keratinocytes; thin transparent band superficial to to the stratum granulosum; only present in thick skin. (Epidermis)
Stratum Corneum (Horny Layer)