Anatomy & Physiology (Chapter 5) Integumentary System PDF

hapter 5 C INTEGUMENTARY SYSTEM SEELEY'S ESSENTIALS OF ANATOMY AND PHYSIOLOGY, 9TH EDITION. Created by: Johmel De Ocampo  Created by: Johmel De Ocampo INTEGUMENTARY SYSTEM The integumentary system...

hapter 5 C INTEGUMENTARY SYSTEM SEELEY'S ESSENTIALS OF ANATOMY AND PHYSIOLOGY, 9TH EDITION. Created by: Johmel De Ocampo  Created by: Johmel De Ocampo INTEGUMENTARY SYSTEM The integumentary system consists of the skin and accessory structures, such as hair, glands, and nails. FUNCTION OF INTEGUMENTARY SYSTEM PROTECTION. The skin provides protection against abrasion and ultraviolet light. It also prevents microorganisms from entering the body and reduces water loss, thus preventing dehydration. SENSATION. The integumentary system has sensory receptors that can detect heat, cold, touch, pressure, and pain. VITAMIN D PRODUCTION. When exposed to ultraviolet light, the skin produces a molecule that can be transformed into vitamin D, an important regulator of calcium homeostasis. TEMPERATURE REGULATION. The amount of blood flow beneath the skin’s surface and the activity of sweat glands in the skin both help regulate body temperature. EXCRETION. Small amounts of waste products are lost through the skin and in gland secretions. SKIN Also known as CUTANEOUS MEMBRANE Covers the external surface of the body Covers an area of about 2 square meters. Weighs 4.5-5kg 7% of total body weight.  Created by: Johmel De Ocampo EPIDERMIS Two Major Tissue KERATINIZATION During their movement, the Layers cells change shape and A. EPIDERMIS chemical composition. The most superficial layer of skin This process is called Layer of epithelial tissue that keratinization because the rests on dermis cells become filled with the Stratified squamous epithelium protein keratin, which makes Avascular them hard. As keratinization proceeds, epithelial cells eventually die and produce an outer layer of dead, hard cells that resists abrasion and forms a permeability barrier. EPIDERMIS EPIDERMIS STRATUM GRANULOSUM STRATUM BASALE Middle of the epidermis The deepest stratum Consists of three to five Consists of SQUAMOUS layers CUBOIDAL or COLUMNAR cells that undergo mitotic divisions about every 19 days. EPIDERMIS STRATUM LUCIDUM EPIDERMIS Present only in thick skin of areas STRATUM SPINOSUM such as fingertips, palms and Superficial to the stratum soles. basale Consists of 4-6 layers of flattened Appear to be covered with clear, dead keratinocytes that thorn-like spines. contain large amounts of keratin Consists of 8-10 layers and thickened plasma membrane.  Created by: Johmel De Ocampo EPIDERMIS EPIDERMIS STRATUM CORNEUM STRATUM CORNEUM DANDRUFF Most superficial stratum of Excessive sloughing of stratum the epidermis corneum cells from the surface of Consists on average of 25 to 30 the scalp. layers of flattened dead keratinocytes Cells are continuously shed and replaced by cells from deeper strata STRATUM CORNEUM STRATUM CORNEUM CALLUS CORN Increased number of layers of the Thickened stratum corneum over stratum corneum due to friction bony prominence that forms a in the skin. cone shape structure. CLINICAL CONNECTION STRATUM CORNEUM PSORIASIS A common and chronic skin disorder in which keratinocytes divide and move more quickly than normal from the stratum basale to the stratum corneum.  Created by: Johmel De Ocampo DERMIS Two Major Tissue Layers B. DERMIS Composed of dense collagenous connective tissue DERMAL PAPILLAE small nippled-shaped structures that project into the under surface of the epidermis Upper part of the dermis Contain many blood vessels that supply the overlying epidermis. SKIN COLOR MELANIN The group of pigments primarily responsible for skin, hair, and eye color. PHEOMELANIN- Yellow to red pigments EUMELANIN- Brown to black pigments Provides protection against ultraviolet light from the sun Produced by melanocytes. SKIN COLOR MELANOCYTES Irregularly shaped cells with many long process that extend between the epithelial cells of the deep part of the epidermis.  Created by: Johmel De Ocampo DERMIS CLINICAL CONNECTION DERMIS STRETCH MARKS A form of internal scarring, can result from the internal damage to dermis that occurs when the skin is stretched to much CLINICAL CONNECTION DERMIS FRECKLES Caused by increased melanin production CLINICAL CONNECTION DERMIS ALBINISM A recessive genetic trait that causes a deficiency or an absence of melanin  Created by: Johmel De Ocampo DERMIS CLINICAL CONNECTION DERMIS VITILIGO The partial or complete loss of melanocytes from patches of skin that produces irregular white spots CLINICAL CONNECTION DERMIS SUN TAN Ultraviolet light in sunlight stimulates melanocytes to increase melanin production CLINICAL CONNECTION DERMIS LINIA NIGRA Hormones such: Estrogen Melanocyte Stimulating Hormone cause an increase in melanin production during pregnancy in the mother  Created by: Johmel De Ocampo SUBCUTANEOUS TISSUE SUBCUTANEOUS TISSUE Also known as HYPODERMIS Loose connective tissue, including adipose tissue that contains about half the body's stored lipids Attaches skin to underlying bone and muscle and supplies it with blood vessels and nerves ADIPOSE TISSUE Functions as padding and insulation ACCESSORY STRUCTURES OF THE SKIN ACCESSORY STRUCTURES OF THE SKIN HAIR Present on most skin surfaces except the palms, palmar surfaces of the fingers, the soles, and the plantar surfaces of the feet.  Created by: Johmel De Ocampo ACCESSORY STRUCTURES ACCESSORY STRUCTURES OF THE SKIN HAIR GROWTH CLINICAL CONNECTION HAIR CHEMOTHERAPY INDUCED HAIR LOSS Chemotherapeutic agents interrupt the life cycle of rapidly dividing cancer cells, such as the hair matrix cells of hair. ACCESSORY STRUCTURES OF THE SKIN ACCESSORY STRUCTURES OF THE SKIN GLANDS GLANDS MAJOR GLANDS OF THE SKIN: MAJOR GLANDS OF THE SKIN: 1. SEBACEOUS GLANDS 2. SWEAT/ SUDORIFEROUS GLANDS Simple, branched acinar glands The cells of these glands release Produces SEBUM sweat, or perspiration, into hair an oily, white substances rich follicles or onto the skin surface in lipids through pores.  Created by: Johmel De Ocampo INTEGUMENTARY SYSTEM INTEGUMENTARY SYSTEM AS A DIAGNOSTIC AID CYANOSIS A bluish color to the skin caused by decreased blood O2 content. an indication of impaired circulatory or respiratory function INTEGUMENTARY SYSTEM AS A DIAGNOSTIC AID JAUNDICE A yellowish skin discoloration When the liver is damaged by a disease. BURNS Injury to a tissue caused by heat, cold, friction, chemicals, electricity or radiation.  Created by: Johmel De Ocampo BURNS PARTIAL-THICKNESS BURN PARTIAL-THICKNESS BURN FIRST DEGREE BURN Part of the stratum basale remains viable, and regeneration Involve only the epidermis of the epidermis occurs from Red and painful within the burn area. Slight edema may be present Subdivided into: They can be caused by sunburn or First degree burn brief exposure to very hot or very Secon degree burn cold objects They heal without scarring in about a week PARTIAL-THICKNESS BURN SECOND DEGREE BURN FULL-THICKNESS BURN Damage both the epidermis and Also known as THIRD DEGREE the dermis BURN Minimal dermal damage: The epidermis and the dermis are Redness, pain, edema & completely destroyed blisters Usually painless Wound appears red, tan or Appear white tan, brown, black white or deep cherry red.  Created by: Johmel De Ocampo BURNS  Created by: Johmel De Ocampo BURNS  Created by: Johmel De Ocampo SKIN CANCER SKIN CANCER Most common type of cancer Most often is associated with exposure to ultraviolet (UV) light from the sun PREDISPOSING FACTOR: Fair-skinned Older than 50 years old THREE MAIN TYPE OF SKIN CANCER BASAL CELL CARCINOMA SQUAMOUS CELL MALIGNANT MELANOMA The most frequent CARCINOMA Rare form of skin type Develops from cancer that arises Begins with cells cells immediately from melanocytes in the stratum superficial to the The melanoma basale and stratum basale can appear as a extends into the If untreated. the large, flat, dermis to produce tumor can invade spreading lesion an open ulcer the dermis, or as a deeply MANAGEMENT: mettastasize pigmented nodule Surgical removal or radiation therapy  Created by: Johmel De Ocampo SKIN DISEASE ECZEMA is an allergic reaction that manifests as dry, itchy patches of skin that resemble rashes. It may be accompanied by swelling of the skin, flaking, and in severe cases, bleeding. Many who suffer from eczema have antibodies against dust mites in their blood, but the link between eczema and allergy to dust mites has not been proven. Symptoms are usually managed with moisturizers, corticosteroid creams, and ACNE immunosuppressants. is a skin disturbance that typically occurs on areas of the skin that are rich in sebaceous glands (face and back). It is most common along with the onset of puberty due to associated hormonal changes, but can also occur in infants and continue into adulthood. Hormones, such as androgens, stimulate the release of sebum. An overproduction and accumulation of sebum along w/ keratin can block hair follicles This plug is initially white. The sebum, when oxidized by exposure to air, turns black. Acne results from infection by acne- causing bacteria (Propionibacterium and Staphylococcus), which can lead to redness and potential scarring due to the natural wound healing process  Created by: Johmel De Ocampo SKIN DISEASE DERMATITIS IMPETIGO RINGWORM DECUBITU ULCER RUBELLA SHINGLES GENITAL HERPES COLD SORES CHICKEN POX  Created by: Johmel De Ocampo SUMMARY FUNCTIONS OF INTEGUMENTARY The integumentary system consists of the skin, hair, glands, and nails. The integumentary system protects us from the external environment. Other functions include sensation, vitamin D production, temperature regulation, and excretion of small amounts of waste products. SKIN EPIDERMIS 1. The epidermis is stratified squamous epithelium divided into strata. New cells are produced in the stratum basale The stratum corneum consist of many layers of dead squamous cells containing keratin. The most superficial layers are sloughed. 2. Keratinization is the transformation of stratum basale cells into stratum corneum cells. Structural strengths result from keratin inside the cells and from desmosomes, which hold the cells together DERMIS 1. The dermis is dense connective tissue. 2. Collagen and elastic fibers provide structural strength, and the blood vessels of the papillae supply the epidermis with nutrients. SKIN COLOR 1. Melanocytes produce melanin, which is responsible for different skin colors. Melanin production is determined genetically but can be modified by exposure to ultraviolet light and by hormones. 2. Carotene, a plant pigment ingested as a source of vitamin A, can cause the skin to appear yellowish. 3. Increased blood flow produces a red skin color, whereas decreased blood flow causes a pale skin color. Decreased blood O2 results in the blue skin color of cyanosis. 4. Scattering of light by collagen produces a bluish color. SUBCUTANEOUS TISSUE 1. The subcutaneous tissue, which is not part of the skin, is loose connective tissue that attaches the skin to underlying tissues. 2. About half of the body’s lipids are stored in the subcutaneous tissue. ACCESSORY SKIN STRUCTURE HAIR 1. Hairs are columns of dead, keratinized epithelial cells. Each hair consists of a shaft (above the skin), a root (below the skin), and a hair bulb (site of hair cell formation). 2. Hairs have a growth phase and a resting phase. 3. Contraction of the arrector pili, which are smooth muscles, causes hair to “stand on end” and produces a “goose bump.”  Created by: Johmel De Ocampo SUMMARY GLANDS 1. Sebaceous glands produce sebum, which oils the hair and the surface of the skin. 2. Eccrine sweat glands produce sweat, which cools the body. 3. Apocrine sweat glands produce an organic secretion that causes body odor when broken down by bacteria. NAILS 1. The nail consists of the nail body and the nail root. 2. The nail matrix produces the nail, which is composed of stratum corneum cells containing hard keratin. PHYSIOLOGY OF INTEGUMENTARY PROTECTION The skin reduces water loss, prevents the entry of microorganisms, and provides protection against abrasion and ultraviolet light; hair and nails also perform protective functions. SENSATION The skin contains sensory receptors for pain, heat, cold, and pressure. VITAMIN D PRODUCTION Ultraviolet light stimulates the production of a precursor molecule in the skin that is modified by the liver and kidneys into vitamin D. Vitamin D increases calcium uptake in the small intestine. TEMPERATURE REGULATION Through dilation and constriction of blood vessels, the skin controls heat loss from the body. Evaporation of sweat cools the body. EXCRETION Skin glands remove small amounts of waste products but are not important in excretion. INTEGUMENTARY AS A DIAGNOSTIC AID The integumentary system is easily observed and often reflects events occurring in other parts of the body (e.g., cyanosis, jaundice, rashes). BURNS 1. Partial-thickness burns damage only the epidermis (first-degree burn) or the epidermis and the dermis (second-degree burn). 2. Full-thickness burns (third-degree burns) destroy the epidermis, the dermis, and usually underlying tissues.  Created by: Johmel De Ocampo SUMMARY SKIN CANCER 1. Basal cell carcinoma involves the cells of the stratum basale and is readily treatable. 2. Squamous cell carcinoma involves the cells immediately superficial to the stratum basale and can metastasize. 3. Malignant melanoma involves melanocytes, can metastasize, and is often fatal. REFERENCE Seeley's Essentials of Anatomy and Physiology, 9th Edition. No Copyright Intended.