1. Integumentary System Dermis

2. 2 layers of skin Epidermis – Surface layer of skin

3. 2 layers of skin Dermis – Underlying layer of skin

4. Skin Layers Strength of skin in Dermis –Collagen fibers Greek for ‘glue producing’ –Elastic fibers

5. Skin Layers Storage area for water

6. Dermis Layers 2 Layers – –Papillary –Reticular

7. Dermis – 2 Layers 1. Papillary layer  Thinner layer

8. Dermis – 2 Layers 1. Papillary layer  Has Dermal papillae – finger-like projections into epidermis

9. Dermal Papillae 1. Papillary layer  Papillae ridges– result in fingerprints  Responsible for grip

10. Dermal Papillae Dermal papillae

11. Dermal Papillae

12. Dermal Layer 2. Reticular layer  Network of fibers or reticulum  Thicker layer  Used for leather

13. Dermal Layer

16.  Muscles attach  Result: Facial expression

17. Dermal Layer  Arrector pili muscle Attach to hair follicle

18. Dermal Layer  During fright – hair stands up  Called “skin crawl”

19. Dermal Layer

20.  Dermal layer doesn’t shed

21. Dermal Layer  Contains sensory receptors Pain Pressure (touch) Heat

22. Dermal Layer  Contains appendages Hair Nail Sweat Sebaceous gland (oil)