Presentation on theme: "The Integumentary System and Body Membranes Chapter 5."— Presentation transcript:
The Integumentary System and Body Membranes Chapter 5
Objectives Classify, compare the structure of, and give examples of each type of body membrane. Describe the structure and function of the epidermis and dermis. List and briefly describe each accessory organ of the skin. List and discuss the three primary functions of the integumentary system.
Question What are the four major types of membranes in the body?
Slide 5 CLASSIFICATION OF BODY MEMBRANES Epithelial membranes –Cutaneous membrane— the skin –More later!!
Classification of Body Membranes Mucous membranes –Line body surfaces that open directly to the exterior –Produce mucus, a thick secretion that keeps the membranes soft and moist keeps the membranes soft and moist What are examples of mucous membranes?
Serous Membranes Line the cavities that do not open to the outside world Double layered –Visceral –Parietal Serous fluid is in the cavity between them
Slide 9 Synovial Membranes 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
Disorders of Body Membranes 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 line the walls and cover the abdominal organs organs
Integumentary System Integument = covering Consists of: –Skin –Accessory Organs: Hair Nails Glands The largest organ of the body is the Skin
Functions of Skin Protects from injuries Acts as barrier and regulates what enters/leaves body. Regulates body temperature. Synthesizes, stores vitamins. Sensory functions
Functions of the Skin Sense organ activity –Skin functions as an enormous sense organ organ –Receptors serve as receivers for the body, keeping it informed of changes in its environment—disorders of the skin (dermatoses)
Functions of the Skin Protection—first line of defense –Against infection by microbes –Against ultraviolet rays from sun –Against harmful chemicals –Against cuts and tears –Skin grafts
Structure of the Skin 3 main layers from superficial to deep 1) Epidermis Epi- derm/o -is aboveskinstructure “structure above the skin” a. Thin cellular membrane layer
3) Subcutaneous tissue Sub-cutane/o-us Belowskinstructure “structure below the skin” a. thick, fat-containing tissue Structure of the Skin (cont’d)
Hypodermis (Subcutaneous) Atlas of Human Anatomy in Cross Section: Section 2. Neck, Shoulders, Upper Arm, and Upper Thorax (Lungs) Key Figure 4 a 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 Recognize d by adipose tissue.
Question What are some of the appendages of the skin?
The Skin Appendages of the skin –Hair Soft hair of fetus and newborn called lanugo Hair growth requires epidermal tube-like structure called hair follicle structure called hair follicle Hair growth begins from hair papilla
The Skin Appendages of the skin –Hair Hair root lies hidden in follicle; visible part of hair called shaft hair called shaft Alopecia hair loss Arrector pili—specialized smooth muscle that produces “goose pimples” and causes hair to stand up straight
The Skin Nails –Produced by epidermal cells over terminal ends of fingers and toes –Visible part called nail body –Root lies in a groove and is hidden by cuticle cuticle –Crescent-shaped area nearest root called lunula –Nail bed may change color with change in blood flow
The Skin Skin glands –Types Sweat or sudoriferous Sebaceous
The Skin Skin glands –Sweat or sudoriferous glands Types –Eccrine sweat gland Most numerous, important, and widespread of the sweat gland widespread of the sweat gland Produce perspiration or sweat, which flows out through pores on skin surface flows out through pores on skin surface Function throughout life and assist in body heat regulation body heat regulation
The Skin Skin glands –Sweat or sudoriferous glands Types –Apocrine sweat gland Found primarily in axilla and around genitalia Secrete a thicker, milky secretion quite different from eccrine perspiration Breakdown of secretion by skin bacteria produces odor
The Skin Skin glands –Sweat or sudoriferous glands Types –Sebaceous gland Secrete oil or sebum for hair and skin Level of secretion increases during adolescence Amount of secretion regulated by sex hormones Sebum in sebaceous gland ducts may darken to form a blackhead Acne vulgaris inflammation of sebaceous gland ducts
The Skin Appendages of the skin –Receptors Specialized nerve endings—make it possible for skin to act as a sense organ for skin to act as a sense organ Meissner’s corpuscle—capable of detecting light touch light touch Pacinian corpuscle—capable of detecting pressure pressure
Quick Quiz Which layer does not have a blood supply?
Quick Quiz Which layer has the pigment cells?
Quick Quiz Which part of the epidermis is undergoing mitosis all the time?
Case Study Katie is a 15-year-old girl who is very upset because of the pimples on her face. She cannot understand why her little sister Kimberly, who is 7, doesn’t have acne.
Question What explanation can you give Katie concerning her skin? A.In several years Kimberly also will have acne. B.Acne is present most likely because she doesn’t wash her face. C.Acne is an allergic reaction to certain creams used on the face. D.Acne in adolescence is a result of overactive sebaceous glands.
Question Katie is embarrassed because of the pimples on her face. Her mother has decided to seek medical attention. What sort of doctor will she probably see? A.dermatologist B.cosmetic specialist C.plastic surgeon D.pediatrician
Question Which of the following statements about hair follicles is true? A.Arrector pili muscles are associated with them. B.Sudoriferous glands empty into them. C.They arise directly from the epidermis layer of skin. D.All of the above.
Slide 44 Burns –Classification of burns 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 Third-degree (full-thickness) burns— characterized by complete destruction of the epidermis and dermis and subcutaneous tissues.
Slide 45 THE SKIN 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 Additional 1% located around genitals
Burns First-degree (partial-thickness) burns—only surface layers of epidermis involved involved Second-degree (partial-thickness) burns—involve the deep epidermal burns—involve the deep epidermal layers and always cause injury to the upper layers of the dermis layers and always cause injury to the upper layers of the dermis
Burns Third-degree (full-thickness) burns (Figure 6-14) characterized by complete destruction of the epidermis, dermis, and subcutaneous tissue (Figure 6-14) characterized by complete destruction of the epidermis, dermis, and subcutaneous tissue –May involve underlying muscle and bone (fourth-degree) –Lesion is insensitive to pain because of destruction of nerve endings immediately after injury—intense pain is soon after injury—intense pain is soon experienced experienced
Skin Lesions Elevated lesions—cast a shadow outside their edges outside their edges –Papule—small, firm raised lesion –Plaque—large raised lesion –Vesicle—blister –Pustule—pus-filled lesion –Crust—scab –Wheal (hive)—raised, firm lesion with a light center light center
Skin Lesions Flat lesions—do not cast a shadow –Macule—flat, discolored region Depressed lesions cast a shadow within their edges –Excoriation—missing epidermis, as in a scratch wound –Ulcer—craterlike lesion –Fissure—deep crack or break
Skin Cancer Three common types –Squamous cell carcinoma—the most common type, characterized by hard, common type, characterized by hard, raised tumors raised tumors –Basal cell carcinoma—characterized by papules with a central crater; rarely spreads spreads –Melanoma—malignancy in a nevus (mole); the most serious type
Skin Cancer The most important causative factor in common skin cancers is exposure to sunlight Kaposi sarcoma, characterized by purple lesions, is associated with AIDS and other immune deficiencies purple lesions, is associated with AIDS and other immune deficiencies
Skin Infections Impetigo—highly contagious staphylococcal infection staphylococcal infection –Tinea—fungal infection (mycosis) of the skin; several forms occur skin; several forms occur –Boils—furuncles; staphylococcal infection in hair follicles in hair follicles –Scabies—parasitic infection
Vascular and Inflammatory Skin Disorders Decubitus ulcers (bedsores) develop when pressure slows down blood flow to local areas of the skin areas of the skin Urticaria or hives—red lesions caused by fluid loss from blood vessels fluid loss from blood vessels Scleroderma—disorder of vessels and connective tissue characterized by hardening of the skin; two types: localized and systemic of the skin; two types: localized and systemic
Vascular and Inflammatory Skin Disorders Psoriasis—chronic inflammatory condition accompanied by scaly condition accompanied by scaly plaques plaques Eczema—common inflammatory condition characterized by papules, vesicles, condition characterized by papules, vesicles, and crusts; not a disease and crusts; not a disease itself but a symptom of an underlying itself but a symptom of an underlying condition condition