1. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Chapter 5 Integumentary System

2. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Integumentary System Skin and its appendages –Hair –Nails –Sebaceous glands –Sweat glands Integumentary means “covering” 3,000 square inches of surface area

3. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Functions of the Skin (1 of 2) Covering Regulate body temperature Manufacture Vitamin D Nerve receptors

4. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Functions of the Skin (2 of 2) Temporary storage of fat, glucose, water and salts Screen out ultraviolet radiation Special absorptive properties

5. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Structure of the Skin Epidermis –Outermost covering –Avascular Dermis –True skin –Connective tissue –Vascular

6. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 5-2 A cross section of the skin

7. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Epidermal Cells Keratinocytes –Produce keratin Merkel cells –Sensory receptors for touch Melanocytes –Produce the pigment melanin Langerhans cells –Macrophages that defend against microorganisms

8. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Epidermal Layers Stratum germinativum –Deepest epidermal layer Stratum spinosum –8-10 cell layers thick Stratum granulosum –Where keratinization occurs Stratum lucidum –Palms and soles Stratum corneum –Dead cell layer

9. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Dermis Also called corium Thicker, inner layer of the skin below the epidermis Many nerve receptors Blood vessels and heat regulation Mast cells respond to injury, infection or allergy and produce histamine and heparin

10. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Subcutaneous Layer Also called hypodermal layer Lies under dermis Not a true part of the integumentary system Attaches integumentary system to the surface muscles underneath

11. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Appendages - Hair Root shaft Outer cuticle layer Cortex Inner medulla Hair follicle Arrector pili muscle

12. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 5-3 The anatomy of an individual hair

13. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Appendages - Nails Hard structures covering the dorsal surfaces of the last phalanges of the fingers and toes Formed in the nail bed or matrix Lunula: white crescent at the proximal end of the nail Diseases and nail color (Table 5.2)

14. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 5-4 Diagram of the fingernail bed

15. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Appendages - Sweat Glands Also called sudoriferous glands Perspiration is 99% water Perspiration is excreted through pores Under the control of the nervous system 500 ml water lost per day through the skin Ceruminous or wax glands found in ear canals

16. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Sebaceous Glands Secrete sebum which is thick, oily substance Sebum lubricates the skin, keeping it soft and pliable

17. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Microorganisms Intact skin is the best way to protect against pathogens Most skin bacteria are associated with hair follicles and sweat glands Hand washing –Most effective action to prevent spread of disease 20 seconds for washing hands 2–4 minutes for infectious material

18. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Aging Skin Becomes more fragile and dry Loss of elasticity Less effective body temperature control Melanocytes decrease Physiological changes can impact self- worth

19. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Skin (1 of 5) Acne vulgaris –Common and chronic disorder of sebaceous glands –Occurs mostly during adolescence and marked by blackheads, cysts, pimples and scarring Athlete’s foot –Contagious fungal infection –Blisters between fingers and toes causing cracking and scaling Dermatitis –Non-contagious inflammation of the skin

20. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Skin (2 of 5) Eczema –Acute or chronic, noncontagious inflammatory skin disease –Dry, red, itchy and scaly Impetigo –Acute, inflammatory, and contagious skin disease –Caused typically by staph or strep –Honey crusted exudates Psoriasis –Chronic inflammatory skin disease (reddish patches covered by silvery-white scales) –Autoimmune disease triggered by stress, trauma or infection

21. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Skin (3 of 5) Ringworm –Highly contagious fungal infection –Red, circular patches with scaly borders Urticaria (hives) –Intensely itchy, red, raised wheals or welts –Response to an allergen Boils (carbuncles) –Painful, bacterial infection of the hair follicles or sebaceous glands –May require an incision and drainage

22. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Skin (4 of 5) Rosacea –Common inflammatory disorder (chronic redness and irritation to the face) –Triggers include stress, caffeine, hot foods, and alcohol Herpes –Viral infection that is usually seen as a blister –Simplex includes cold sores involving the lips or beneath the nose

23. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Skin (5 of 5) Genital herpes –Virus that may appear as a blister in the genital area –Discussed in Chapter 21 Shingles (herpes zoster) –Skin eruption due to a viral infection of the nerve ending –Reactivation of the chicken pox virus (varicella)

24. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Hair and Nails (1 of 2) Head lice –Parasitic insects –Intense itching and sores on the head Ingrown nails –Common nail problem

25. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Disorders of the Hair and Nails (2 of 2) Fungal infections –Infections of the nail –Makes up 50% of all nail problems Warts –Viral infections that affect the skin surrounding or underneath the nail –Caused by human papilloma virus (HPV)

26. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Skin Cancer Basal cell carcinoma –Most common and least malignant Squamous cell carcinoma –Most often found on the scalp and lower lip Malignant melanoma –Metastasizes to other areas quickly –Change in color, size, shape of a mole Skin and sun exposure

27. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Burns Rule of nines –Percent of the body burned First-degree burns –Superficial, epidermis only, no blister, redness swelling and pain Second-degree burns –Epidermis and dermis, blister forms Third-degree burns –Complete destruction of epidermis, dermis and subcutaneous layers forming an eschar (black skin)

28. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Skin Lesions Pressure ulcer (decubitus ulcers) –Stage I –Redness only, skin intact –Stage II –Blistered skin, broken or unbroken –Stage III –Skin breaks through all layers –Stage IV –Ulceration to underlying muscle and bone

29. © 2017 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. Figure 5-10 Different types of skin lesions