1. Integumentary System

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 Membranes
Cutaneous – (skin); only epithelial membrane that is dry

5. Integumentary System Most roles are protective
Helps maintain homeostasis
Insulates body
Keeps water and molecules in body
Protects organs from bumps, cuts, etc.

6. Make-up of epidermis Epidermis has no blood supply (avascular)
Most cells are keratinocytes
Produce keratin (tough fibers which make skin tough but pliable)

7. Stratum Basale Basement membrane of epidermis Vascularized
Constantly undergoing mitosis
By the time cells reach the surface, they are dead.

8. Melanin
Cells in stratum basale take in melanocytes (cells produce pigment)
Melanin = body’s natural sunscreen

9. Dermis Layer directly beneath the epidermis Highly Vascularized
Connective tissue

10. Make-up of Dermis Mostly collagen and elastic fibers
Fibers bind with water and keep skin hydrated
Fibers decrease with age, and skin sags

11. Deep to the Dermis Subcutaneous layer Also called hypodermis
Adipose tissue
Absorbs impact from bumps, protects organs; insulation

13. Skin Cancer
Melanin serves to protect cellular DNA from ultraviolet light
When damage is done to DNA, cancer can occur
Basal Cell carcinoma (least malignant)
Squamous cell carcinoma
Melanoma – darkened blotches
Cancer of the melanocyte

14. Papillary Layer Upper dermal region
Protrusions into epidermis called dermal papillae
Nourishes epidermis

15. Also in Papillary Layer
Meissner’s corpuscles – sensory receptors (touch)
Pain receptors
Papillary 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 sebum
Sebum keeps skin moist and pliable
Also produces acidic compounds that kill bacteria

19. Problems with oil glands
Clogged oil gland becomes whitehead
As whitehead oxidizes, it becomes darker (blackhead)
Acne – infection of oil gland
Seborrhea- “cradle cap”