BIOD 151 Module 7 - Integumentary System (Summary).

BIOD 151 Module 7 - Integumentary System (Summary). layers of skin 1. Epidermis 2. Dermis 3. Hypodermis (subcutaneous layer) function of skin 1. absorb UV light for vitamin D production 2. sensory receptors and glands 3. protection from temp. changes 4. protect from miroorganisms sensory organs 1. merkel cells 2. missener's corpuscles 3. nociceptors 4. thermoreceptors 5. pacinian corpuscles merkel cells mechanoreceptors detect mechanical sensory information of light touch superficial - epidermis meissener's corpuscles mechanoreceptors detect mechanical sensory information of light touch and vibrations nociceptors pain receptors - several different types thermoreceptors temperature sensory - hot and cold changes pacinian corpuscles mechanical - pressure applied to skin exocrine glands Glands that secrete substances outward through a duct sebaceous glands produce sebum - prevent skin from drying out and cracking - prevent growth of microorganisms sudoriferous glands produce sweat (perspiration) - regulation of body temperature multicellular glands set within epithelial tissue and release their contents through a duct to the surface layers of epidermis 1. stratum corneum 2. stratum granulosum 3. stratum spinosum 4. stratum basale *basement membrane C-ome G-et S-un B-urned epidermis - stratified squamous epithelium - avascular - 4 layers - adhered to basement membrane (between epidermis and dermis) Cell renewal 1. cells of stratum basale divide and push toward skin surface 2. superficial layer of stratum contains dead cells that slough off after ~2 weeks at surface - renewal of skin cells ~30 days