1. HS1 integumentary system

2. 7 Functions 1. Protection 2. Regulates body temperature
3. Manufactures Vitamin D
4. Sensory perception
5. Temporary storage of fat, glucose, water and salts
6. Screens out harmful ultraviolet radiation
7. Absorbs certain drugs

3. Layers of your Skin

4. 3 Layers of your Skin 1. Epidermis 2. Dermis 3. Subcutaneous tissue
Outermost covering
Epithelial cells
Avascular
2. Dermis
True skin
Connective tissue
Vascular
3. Subcutaneous tissue

5. Layers broken down….

6. Layers of the Skin
Epidermis

7. EPIDERMIS Thickness varies on location *thinnest on eyelids
*thickest on palms of hands & soles of feet.

8. EPIDERMIS 4 cell types Keratinocytes
produces keratin which keeps skin dry and is a barrier to UV & bacteria
2. Merkel Cells
Sensory receptors for touch
3. Melanocytes
Make protein “melanin” – give you your color. The more melanin the darker you are
Freckles = patches of melanin
4. Langerhans Cells
defend microorganisms

9. Epidermis cont… 5 layers Stratum Germinativum (deepest)
Stratum Spinosum
Stratum Granulosum (keratinization begins & cells die)
Stratum Lucidum
Stratum Corneum

10. Epidermis cont… Lower edge of layer #1 has ridges known as “papillae”
- very pronounced in fingers/soles/palms
-provide resistance to slipping for holding/grasping objects
-create individual fingerprints & footprints.

11. Layers of the Skin Cont….
Dermis

12. Dermis Consists of Connective Tissue Collagen tissue bands
Elastic fibers
Nerve endings
Muscles
Hair follicles
Oil & sweat glands
Fat Cells
Thickest over soles of feet & palms of hands

13. Dermis cont… Contains nerve receptors
• Sensory nerves – heat, cold, touch, pain and pressure
• Touch receptors close to the surface
• Pressure receptors are deeper
Blood vessels in dermis aid in the regulation of body temp. An or in outside temp makes blood vessels dilate to bring warmed blood flow to the surface of your body.

14. Layers of the Skin Cont…
*Subcutaneous

15. Subcutaneous Also called “Superficial fascia” or “Hypodermal” Layer
Not a true part of integumentary system (attaches dermis to surface muscles)

16. Subcutaneous Consists of loose connective tissue
Contains ½ of body's stored fat.
Some injections can be given here (abbreviated SQ – given at 45 degree angle)

17. Appendages of the Skin
Includes Hair, Nails, Sweat Glands, & Oil Glands

18. Appendages of the Skin
Hair

19. Hair Almost everywhere on the body
(except palms, soles, glans penis, & inner vaginal labia)
Length, thickness, type and color varies

20. Hair Length, thickness, type and color varies
Outer layer = CORTEX (as one ages, pigment replaced with air and looks white/gray)
Inner layer = MEDULLA
Part under the skin = ROOT
Part outside the skin = SHAFT (protects skin surface)

21. Hair cont…
FOLLICLE = pocket in epidermis, hair inside (determines straight or curly hair)
PAPILLA = tuft of tissue in root, contains capillaries
ARRECTOR PILI MUSCLE = attached on side of each follicle, when stimulated by a sudden chill it contracts and causes skin to pucker “Goosebumps”

22. Appendages of Skin
Nails

23. Nails Formed in the nail bed “matrix”
Epidermal cells fuse together and fill with keratin

24. Sweat Glands “SUDORIFEROUS GLANDS”
Appendages of Skin
Sweat Glands “SUDORIFEROUS GLANDS”

25. Sweat Glands Perspiration = sweat (99% water)
Distributed over the entire skin surface
Large numbers under the arms, palms of hands, soles of feet and forehead

26. Sweat Glands
Duct extends to form a pore in the skin, perspiration excreted through the pores
May be activated by heat, pain, fever and nervousness
Average fluid loss is 500 ml per day

27. Oil Glands “Sebaceous Glands”
Appendages of Skin
Oil Glands “Sebaceous Glands”

28. Oil glands Secret oil (SEBUM) that protects and lubricates the skin
Keeps skin soft & pliable