CHAPTER 20 The Integumentary System © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-2 Learning Outcomes 20.1 List the functions of skin 20.2 Explain the role of skin in regulating body temperature 20.3 Describe the layers of skin and the characteristics of each layer 20.4 Explain the factors that affect skin color 20.5 Identify and describe common skin lesions © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-3 Learning Outcomes (cont.) 20.6 List the accessory organs of skin and describe their structures and functions 20.7 Explain the process of skin healing, including scar production 20.8 Describe the effects of aging on skin 20.9 List the different types of burns and describe their appearances and treatments © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-4 Learning Outcomes (cont.) 20.10 Describe the causes, signs and symptoms, and treatments of various types of skin cancer 20.11 Describe the causes, signs and symptoms, and treatments of common skin disorders 20.12 Explain the ABCDE rule and its use in evaluating melanoma 20.13 Using the acronym CAUTION, list the seven warning signs of cancer © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-5 Introduction • Integumentary system consists of skin and its accessory organs • Accessory organs: – Hair follicles – Nails – Skin glands Skin is the body’s outer covering and its largest organ © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-6 Functions of the Integumentary System • Protection – First line of defense against • • Bacteria Viruses – Protects underlying structures from • • Ultraviolet (UV) radiation Dehydration © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d Functions of the Integumentary System 20-7 (cont.) • Body temperature regulation – If too hot • • Dermal blood vessels dilate Vessels carry more blood to surface so heat can escape – If too cold • • Dermal blood vessels constrict Prevents heat from escaping © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d Functions of the Integumentary System 20-8 (cont.) • Vitamin D production – Needed for calcium absorption • Sensation – Sensory receptors • Excretion – Small amounts of waste products are lost through perspiration © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-9 Apply Your Knowledge What are the functions of the integumentary system? ANSWER: The functions of the integumentary system are protection, regulation of body temperature, vitamin D production, sensation, and excretion Super! © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-11 Epidermis • Most superficial layer • Two parts – Stratum corneum • Outermost layer • Mostly dead cells form an impermeable layer – Stratum basale (stratum germinativum) • Deepest layer • Cells constantly dividing and pushing older cells outward To Figure of Skin © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-43 Malignant Melanoma • Signs and Symptoms – From melanocytes – Appear on trunk, head, neck of men – Appear on arms and legs of women – Itches or bleeds • Treatment – Surgery and biopsy – Removal of lymph nodes – Chemotherapy and radiation therapy – Immunotherapy © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-44 Stages of Melanoma Stage Only found in epidermis Stage I Spread to epidermis and dermis (1 to mm thick) Stage II to mm thick plus ulceration Stage III Spread to one or more lymph nodes Stage IV Spread to other body organs or lymph nodes far from original melanoma © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-45 ABCDE Rule A Asymmetry – a mole should not become asymmetrical It should look equal in size from side to side B C D Border – a mole should not have irregular borders and edges should not blur into normal tissue E Evolving – a mole that has been changing in size, color and appearance, or growing in an area of previously normal skin Color – a mole should not change or become mixture of colors It should have even coloring Diameter – a mole should not grow larger than the diameter of a pencil eraser (6 mm.) © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-46 24-46 Cancer Warning Signs C– A– U– T– I – O– N– Change in bowel or bladder habits A sore that will not heal Unusual bleeding or discharge Thickening or lump Indigestion or difficulty swallowing Obvious change in wart or mole Nagging cough or hoarseness © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-47 Apply Your Knowledge True or False: ANSWER: F Basal cell carcinoma is the most aggressive form of skin _ cancer and can form anywhere Melanomas are more aggressive T _ Squamous cell carcinoma is more likely to spread to T surrounding tissues _ Lesions of melanoma appear on trunk, head, neck of F men and on arms and legs of women are irregular _ The borders Borders of skin cancers are usually regular T _ Basal cell carcinoma progresses slowly and rarely spreads to other body parts © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-48 Common Skin Disorders Alopecia • –  Results in hair loss Dermatitis  Cellulitis • – Inflammation of connective tissue in skin  Eczema   Inflammation of skin or a rash Chronic dermatitis Folliculitis  Inflammation of hair follicles © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-49 Common Skin Disorders • Herpes simplex • – Type – cold sores – Type – genital • Herpes zoster – Shingles • Impetigo (cont.) Pediculosis – Head lice – Body lice – Pubic lice • Psoriasis – Inherited autoimmune disorder – Oozing skin lesions that eventually crust over © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-50 Common Skin Disorders • Ringworm – Tinea corporis – Tinea capitis – Tinea pedis • Rosacea – Dilation of small facial blood vessels (cont.) • Scabies – Contagious skin condition caused by mites • Warts – Harmless growths caused by a virus © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-51 Apply Your Knowledge Match the following: ANSWER: C Alopecia _ A Dilation of small facial blood vessels E Folliculitis _ B Inherited autoimmune disorder F Impetigo _ C Hair loss B Psoriasis _ D Growths caused by a virus A Rosacea _ E Inflammation of hair follicles D Warts _ F Oozing skin lesions Right! © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-52 In Summary 20.1 The functions of skin include protection, body temperature regulation, vitamin D production, sensation, and excretion 20.2 When the body is warm, the dermal blood vessels dilate, allowing heat to escape and cool the body When the body is cool, the same vessels constrict, preventing the heat carried by blood from escaping, keeping the body warmer 20.3 The topmost layer of the skin is the epidermis The dermis is the complex middle layer The innermost layer, attaching the skin to muscle, is the subcutaneous layer © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-53 In Summary (cont.) 20.4 The amount of melanin affects and determines skin color The amount of oxygen-carrying hemoglobin in our blood also affects skin color 20.5 Skin lesions are split among three main types: primary lesions such as macules and vesicles; secondary lesions include ulcers and keloids; vascular lesions involve blood vessels and include telangiectasias and ecchymoses 20.6 The accessory organs of skin include hair follicles, arrector pili muscles, sebaceous glands, sudoriferous glands, and keratin-filled nails © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-54 In Summary (cont.) 20.7 Injured skin becomes inflamed from dilating blood vessels which leak and cause swelling A blood clot is formed, which is replaced by a scab, which is then replaced by collagen fibers that produce scar tissue 20.8 Skin loses elasticity with aging as well as the youthful glow because of the loss of collagen and elastin fibers The loss of melanin also causes graying and thinning of the hair The loss of adipose tissue and decreased number of sudoriferous glands makes it difficult to readily adjust to temperature changes © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-55 In Summary (cont.) 20.9 First-degree burns affect only the epidermis and are known as superficial burns Second-degree burns or partial thickness burns involve both the epidermis and dermis Third-degree or full-thickness burns affect all skin layers and underlying structures, including muscle and bone 20.10 There are three types of skin cancer: basal cell, squamous cell, and malignant melanoma Signs of skin cancer vary, as the treatment methods for each type © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-56 In Summary (cont.) 20.11 Common skin disorders: the signs, symptoms, and treatments for these conditions are found in the Pathophysiology section at the end of the chapter 20.12 ABCDE is the acronym used to remember the signs of possible melanoma when looking at suspicious moles on the body A = Asymmetry, B = Border, C = Color, D = Diameter, and E = Evolving 20.13 The seven warning signs of cancer are: C = Change, A = A sore, U = Unusual, T = Thickening, I = Indigestion, O = Obvious change, and N = Nagging cough © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20-57 End of Chapter 20 We may have different religions, different languages, different colored skin, but we all belong to one human race ~ Kofi Annan © 2011 The McGraw -Hill Com panies, Inc A ll rights reserv e d [...]... ends of fingers and toes – Hard keratin Diagram © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 26 Accessory Organs (cont.) • Sudoriferous (sweat) glands – Located in the dermis of skin – Types • Eccrine gland – Produce watery type of sweat – Activated by heat • Apocrine gland – Produce thicker type of sweat with more proteins – Concentrated in armpit and groin areas – Activated by... plus – Sudoriferous (sweat) glands – Sebaceous (oil) glands – Hair follicles and arrector pili muscles – Collagen, elastin, and nerve fibers – Blood vessels • Binds the epidermis to the subcutaneous tissue To Figure of Skin © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 14 Subcutaneous Layer • Hypodermis • Composed of – Adipose (fat) and loose connective tissue – Blood vessels and. .. for skin repair, and defensive cells to the area of injury Correct © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 31 Skin and Aging • Skin loses firmness due to – Loss of elastin and collagen fibers in dermis – Loss and shifting of underlying adipose tissues • Skin color changes – Dermis becomes thinner and more transparent – Paler due to decrease in circulation © 201 1 The McGraw... tissue loss © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 25 Accessory Organs • Hair follicles – Tube-like depressions in the dermis of skin – Generate hairs – Alopecia (baldness) occurs when follicles die – Arrector pili muscles attached to follicles cause goose bumps • Sebaceous glands – Produce sebum to keep hair soft – Prevent bacteria from growing on skin • Nails – Protect the... ll rights reserv e d 20- 32 Skin and Aging (cont.) • Melanocytes decrease – Those remaining gather  “age” spots – Hair grays and becomes thinner • Decreased tolerance to temperature changes – Sudoriferous glands decrease in number • Decreased perspiration, hard to adjust to high temperatures – Loss in adipose tissue and decreased circulation • Increased sensitivity to cold © 201 1 The McGraw -Hill... burn – Extent of body surface area – 11 body areas Rule of Nines © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 35 Back © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 36 Burn Severity Burns © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 37 1st Degree Degree 2nd Degree 3rd Back © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 38.. .20- 12 Epidermis (cont.) • Keratinocyte – most common – Makes and accumulates keratin • Durable protein that makes the epidermis waterproof and resistant to pathogens • Melanocyte – Makes the pigment melanin • Traps UV radiation and prevents damage to underlying layers of the skin © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 13 Dermis • Deeper of the... Blood vessels and nerves • Functions – Storage in adipose tissue – Cushions and insulates underlying structures To Figure of Skin © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 15 Apply Your Knowledge Where are melanocytes and keratinocytes, and what is their function? ANSWER: Both are located in the epidermis of the skin Keratinocytes make and accumulate keratin, which is a durable... color? ANSWER: The amount of melanin produced by the melanocytes and the oxygenation of the blood Nice Job! © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 19 Skin Lesions • Any variation in the skin – As simple as a freckle – As serious as a tumor © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 20 Skin Lesions (cont.) Lesion Name Description Bulla A large blister... Diagram © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 28 Skin Healing • Injury  inflammation – Redness due to dilation of nearby blood vessels – Swelling because vessels leak fluid into spaces between cells – Pain because excess fluid activates pain receptors © 201 1 The McGraw -Hill Com panies, Inc A ll rights reserv e d 20- 29 Skin Healing (cont.) • Inflammation promotes healing – Extra