Slide 1 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. Chapter 5 The Integumentary System and Body Membranes

Slide 2 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. CLASSIFICATION OF BODY MEMBRANES  Classification of body membranes (Figure 5-1)  Epithelial membranes—composed of epithelial tissue and an underlying layer of connective tissue  Connective tissue membranes—composed largely of various types of connective tissue

Slide 3 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 4 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. CLASSIFICATION OF BODY MEMBRANES (cont.)  Epithelial membranes  Cutaneous membrane—the skin  Serous membranes—simple squamous epithelium on a connective tissue basement membrane Types Types  Parietal—line walls of body cavities  Visceral—cover organs found in body cavities Examples Examples  Pleura—parietal and visceral layers line walls of thoracic cavity and cover the lungs  Peritoneum—parietal and visceral layers line walls of abdominal cavity and cover the organs in that cavity Diseases Diseases  Pleurisy—inflammation of the serous membranes that line the chest cavity and cover the lungs  Peritonitis—inflammation of the serous membranes in the abdominal cavity that line the walls and cover the abdominal organs

Slide 5 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. CLASSIFICATION OF BODY MEMBRANES (cont.)  Epithelial membranes (cont.)  Mucous membranes Line body surfaces that open directly to the exterior Line body surfaces that open directly to the exterior Produce mucus, a thick secretion that keeps the membranes soft and moist Produce mucus, a thick secretion that keeps the membranes soft and moist

Slide 6 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. CLASSIFICATION OF BODY MEMBRANES (cont.)  Connective tissue membranes  Do not contain epithelial components  Produce a lubricant called synovial fluid  Examples are the synovial membranes in the spaces between joints and in the lining of bursal sacs

Slide 7 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN  Structure (Figure 5-2)—two primary layers called epidermis and dermis  Epidermis Outermost and thinnest primary layer of skin Outermost and thinnest primary layer of skin Composed of several layers of stratified squamous epithelium Composed of several layers of stratified squamous epithelium Stratum germinativum—innermost layer of cells that continually reproduce; new cells move toward the surface (Figure 5-3) Stratum germinativum—innermost layer of cells that continually reproduce; new cells move toward the surface (Figure 5-3) As cells approach the surface, they are filled with a tough, waterproof protein called keratin; eventually cells flake off As cells approach the surface, they are filled with a tough, waterproof protein called keratin; eventually cells flake off Stratum corneum—outermost layer of keratin-filled cells Stratum corneum—outermost layer of keratin-filled cells  Skin pigment—deepest epidermal layer is responsible for production of pigment, which gives color to the skin The brown pigment melanin is produced by specialized cells in this layer The brown pigment melanin is produced by specialized cells in this layer Blisters—caused by breakdown of union between cells or primary layers of skin Blisters—caused by breakdown of union between cells or primary layers of skin

Slide 8 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 9 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 10 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Structure (cont.)  Dermal-epidermal junction—specialized area between two skin layers  Dermis Deeper and thicker of the two primary skin layers and composed largely of connective tissue Deeper and thicker of the two primary skin layers and composed largely of connective tissue Upper papillary layer of dermis characterized by parallel rows of tiny bumps called dermal papillae Upper papillary layer of dermis characterized by parallel rows of tiny bumps called dermal papillae Ridges and grooves in dermis form pattern unique to each individual Ridges and grooves in dermis form pattern unique to each individual  Basis of fingerprinting  Improves grip for tool use and walking Deeper reticular layer of dermis filled with network of tough, interlacing, collagenous and stretchable elastic fibers Deeper reticular layer of dermis filled with network of tough, interlacing, collagenous and stretchable elastic fibers  Number of elastic fibers decreases with age and contributes to wrinkle formation (Figure 5-4)  Dermis also contains nerve endings, muscle fibers, hair follicles, sweat and sebaceous glands, and many blood vessels

Slide 11 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 12 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Accessory structures of the skin  Hair (Figure 5-5) Soft hair of fetus and newborn is called lanugo Soft hair of fetus and newborn is called lanugo Hair growth requires epidermal tubelike structure called hair follicle Hair growth requires epidermal tubelike structure called hair follicle Hair growth begins from hair papilla Hair growth begins from hair papilla Hair root lies hidden in follicle and visible part of hair called shaft Hair root lies hidden in follicle and visible part of hair called shaft Arrector pili—specialized smooth muscle that produces “goose bumps” and causes hair to stand up straight Arrector pili—specialized smooth muscle that produces “goose bumps” and causes hair to stand up straight

Slide 13 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 14 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Accessory structures of the skin (cont.)  Receptors (Figure 5-2) Specialized nerve endings—make it possible for skin to act as a sense organ Specialized nerve endings—make it possible for skin to act as a sense organ Meissner’s corpuscle—capable of detecting light touch Meissner’s corpuscle—capable of detecting light touch Pacini corpuscle—capable of detecting pressure Pacini corpuscle—capable of detecting pressure

Slide 15 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 16 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Accessory structures of the skin (cont.)  Nails (Figure 5-6) Produced by epidermal cells over terminal ends of fingers and toes Produced by epidermal cells over terminal ends of fingers and toes Visible part is called nail body Visible part is called nail body Root lies in a groove and is hidden by cuticle Root lies in a groove and is hidden by cuticle Crescent-shaped area nearest root is called lunula Crescent-shaped area nearest root is called lunula Nail bed may change color with change in blood flow Nail bed may change color with change in blood flow

Slide 17 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 18 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Accessory structures of the skin (cont.)  Skin glands Types Types  Sweat or sudoriferous  Sebaceous Sweat or sudoriferous glands Sweat or sudoriferous glands  Types –Eccrine sweat glands –Most numerous, important, and widespread of the sweat glands –Produce perspiration or sweat, which flows out through pores on skin surface –Function through life and assist in body heat regulation

Slide 19 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Sebaceous glands  Secrete oil or sebum for hair and skin  Level of secretion increases during adolescence  Amount of secretion is regulated by sex hormones  Sebum in sebaceous gland ducts may darken to form blackhead  Sweat or sudoriferous glands (cont.)  Types –Apocrine sweat glands Found primarily in axilla and around genitalia Found primarily in axilla and around genitalia Secrete a thicker secretion quite different from eccrine perspiration Secrete a thicker secretion quite different from eccrine perspiration Breakdown of secretion by skin bacteria produces odor Breakdown of secretion by skin bacteria produces odor

Slide 20 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Skin cancer (Figure 5-7)  Types Squamous cell carcinoma Squamous cell carcinoma Basal cell carcinoma Basal cell carcinoma Malignant melanoma Malignant melanoma Kaposi sarcoma Kaposi sarcoma  Causes Genetic predisposition Genetic predisposition Sun's ultraviolet (UV) radiation damages skin cell DNA, causing mistakes during mitosis Sun's ultraviolet (UV) radiation damages skin cell DNA, causing mistakes during mitosis

Slide 21 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 22 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Skin cancer (cont.)  Squamous cell carcinoma Common type of skin cancer Common type of skin cancer Slow growing Slow growing Lesions begin as painless, hard, raised nodules Lesions begin as painless, hard, raised nodules Will metastasize Will metastasize  Basal cell carcinoma (most common type of skin cancer) Originates in cells at base of epidermis—often on upper face Originates in cells at base of epidermis—often on upper face Lesions begin as small raised areas that erode in center, bleed, and crust over Lesions begin as small raised areas that erode in center, bleed, and crust over Less likely to metastasize than other skin cancer types Less likely to metastasize than other skin cancer types

Slide 23 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Skin cancer (cont.)  Malignant melanoma Most serious form of skin cancer Most serious form of skin cancer May develop from benign, pigmented moles or excess UV radiation May develop from benign, pigmented moles or excess UV radiation Incidence in the United States is increasing Incidence in the United States is increasing ABCD rule of self-examination (Table 5-1) ABCD rule of self-examination (Table 5-1)

Slide 24 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 25 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Functions of the skin  Protection—first line of defense against: Infection by microbes Infection by microbes Ultraviolet rays from sun Ultraviolet rays from sun Harmful chemicals Harmful chemicals Cuts and tears Cuts and tears  Temperature regulation Skin can release almost 3000 calories of body heat per day Skin can release almost 3000 calories of body heat per day  Mechanisms of temperature regulation –Regulation of sweat secretion –Regulation of flow of blood close to the body surface

Slide 26 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Functions of the skin (cont.)  Sense organ activity Skin functions as an enormous sense organ Skin functions as an enormous sense organ Receptors serve as receivers for the body, keeping it informed of changes in its environment Receptors serve as receivers for the body, keeping it informed of changes in its environment

Slide 27 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Burns  Treatment and recovery or survival depend on total area involved and severity or depth of the burn  Body surface area is estimated using the “rule of nines” (Figure 5-8) in adults Body is divided into 11 areas of 9% each Body is divided into 11 areas of 9% each Additional 1% located around genitals Additional 1% located around genitals

Slide 28 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.

Slide 29 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc. THE SKIN (cont.)  Burns (cont.)  Classification of burns (Figure 5-9) First-degree (partial-thickness) burns—only the surface layers of epidermis involved First-degree (partial-thickness) burns—only the surface layers of epidermis involved Second-degree (partial-thickness) burns—involve the deep epidermal layers and always cause injury to the upper layers of the dermis Second-degree (partial-thickness) burns—involve the deep epidermal layers and always cause injury to the upper layers of the dermis Third-degree (full-thickness) burns—characterized by complete destruction of the epidermis and dermis Third-degree (full-thickness) burns—characterized by complete destruction of the epidermis and dermis  May involve underlying muscle and bone  Lesion is insensitive to pain because of destruction of nerve endings immediately after injury—intense pain is soon experienced  Risk of infection is increased

Slide 30 Mosby items and derived items © 2012 by Mosby, Inc., an affiliate of Elsevier Inc.