1. THE INTEGUMENTARY SYSTEM
Skin and its Derivatives

2. TYPES OF MEMBRANES Epithelial + Connective Tissue Connective Tissue
Serous
Cutaneous
Mucous
Connective Tissue
Synovial

3. Serous Membranes Line body cavities that have no openings to outside.
Secrete watery fluid.
Simple squamous epith + loose CT

4. Mucous Membranes Line cavities that lead to outside.
Secrete mucus for protection.
Epithelium + Loose CT

5. Serous, Mucous Membranes

6. Synovial Membrane Lines joint cavities at articulations.
Loose CT + elastic fibers + adipose tissue

7. Cutaneous Membrane
Stratified squamous epithelium + CT + muscle + nervous tissue

8. Functions of Skin Protects from injuries
Acts as barrier and regulates what enters/leaves body.
Regulates body temperature.
Synthesizes, stores vitamins.
Sensory functions

9. EPIDERMIS Stratum corneum Stratum granulosum Stratum spinosum
Stratum lucidum**
Stratum granulosum
Stratum spinosum
Stratum basale (germinativum)
**Thick skin only

10. Stratum Basale Lowest epidermal layer, near dermis
Good nutrient supply
Reproduces by mitosis
Cuboidal, columnar in shape
Moves to upper epidermis in 27 days.

11. Stratum Basale

12. Stratum Spinosum Living cells Dividing 8-10 cells thick
Polygonal in appearance

13. Stratum Spinosum

14. Stratus Granulosum, Lucidum
Poor nutrient supply.
Flatten layer of cells.
3-5 cells thick.
No cell division.
Keratin accumulates.
Found only in very thick skin.
Translucent.
Highly keratinized.
Dead cells

15. Stratum Corneum 25-30 cells thick.
Cells are filled with keratin and hardened.
Sloughed off.
Outer most layer of epidermis.
Keratinocytes

16. Anatomy A215: EPIDERMIS LAYERS Memory Matrix
Superficial or Deep Layer?
Characteristics
Are cells keratinized in this layer?
Seen in THIN skin too?
Stratum Basale
Stratum Spinosum
Stratum Granulosum
Stratum Lucidum
Stratum Corneum

17. DERMIS
                                                                
Irregular Dense Connective Tissue
Collagenous fibers

18. Dermis
Sweat gland
Sebaceous gland
Arrector pili muscle
Blood vessels

19. Hair Follicle

20. Sebaceous Gland

21. Hair Follicles

22. Sweat Gland

23. Types of Sweat Glands (Sudoriferous Glands)
Merocrine glands: release fluid by exocytosis
Eccrine
Most common
Secretion is mostly water with solutes
Cools body down
Apocrine
Develops scent as bacteria metabolize secretion
Stimulated when frightened, during pain, during emotional upset

24. Hypodermis (Subcutaneous)
                                                                      
Atlas of Human Anatomy in Cross Section: Section 2. Neck, Shoulders, Upper Arm, and Upper Thorax (Lungs)
Key Figure 4a
Ronald A. Bergman, Ph.D., Adel K. Afifi, M.D., Jean J. Jew, M.D., and Paul C. Reimann, B.S. Peer Review Status: Externally Peer Reviewed
                                                            
Hypodermis (Subcutaneous)
Recognized by adipose tissue.

25. Sensory Structures of Dermis
Deep touch/pressure: Pacinian corpuscles
Light touch/pressure: Meisner’s corpuscles
Warm temperature: Free nerve endings
Cold temperature: Free nerve endings
Pain: Free nerve endings

26. Melanocyte

27. Melanocyte Produces melanin for protection from UV radiation.
Responsible for skin color.
Melanoma.

28. Melanoma
                                                    

29. Basal Cell Carcinoma

30. Untreated…..

31. Actinic Keratosis Caused by sun damage. Can lead to
squamous cell carcinoma.

32. PSORIASIS

33. MAP SHOWING SKIN COLOR
DISTRIBUTION

34. EVOLUTION OF SKIN COLOR
Balance between
Need for protection against UV radiation which
Causes skin cancer
Destroys folate (vitamin B)
Need for UV to produce vitamin D for calcium absorption