2 SAP2. Students will analyze the interdependence of the integumentary, skeletal, and muscular systems as these relate to the protection, support and movement of the human body.
3 a. Relate the structure of the integumentary system to its functional role in protecting the body and maintaining homeostasis.EQ: What role does the integumentary system play in protecting the body and maintaining homeostasis?
4 Cutaneous MembranesCutaneous – (skin); only epithelial membrane that is dry
5 Integumentary System Most roles are protective Helps maintain homeostasisInsulates bodyKeeps water and molecules in bodyProtects organs from bumps, cuts, etc.
6 Make-up of epidermis Epidermis has no blood supply (avascular) Most cells are keratinocytesProduce keratin (tough fibers which make skin tough but pliable)
7 Stratum Basale Basement membrane of epidermis Vascularized Constantly undergoing mitosisBy the time cells reach the surface, they are dead.
8 MelaninCells in stratum basale take in melanocytes (cells produce pigment)Melanin = body’s natural sunscreen
13 Skin CancerMelanin serves to protect cellular DNA from ultraviolet lightWhen damage is done to DNA, cancer can occurBasal Cell carcinoma (least malignant)Squamous cell carcinomaMelanoma – darkened blotchesCancer of the melanocyte
14 Papillary Layer Upper dermal region Protrusions into epidermis called dermal papillaeNourishes epidermis
15 Also in Papillary Layer Meissner’s corpuscles – sensory receptors (touch)Pain receptorsPapillary pattern is genetic, and forms fingerprint
16 Reticular Layer Deep to papillary layer Contains blood vessels, sweat glands and oil glands.Phagocytes prevent bacterial intrusion
17 Sweat Glands Controlled by nervous system Two types 1) Eccrine 2)Appocrine
18 Sebaceous Glands Oil Glands Ducts usually empty into a hair follicle Secretes sebumSebum keeps skin moist and pliableAlso produces acidic compounds that kill bacteria
19 Problems with oil glands Clogged oil gland becomes whiteheadAs whitehead oxidizes, it becomes darker (blackhead)Acne – infection of oil glandSeborrhea- “cradle cap”