View
213
Download
0
Category
Preview:
Citation preview
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Chapter 6
The Skin in Health The Skin in Health and Diseaseand Disease
Martin Ponciano, LVN, MS, DSDMartin Ponciano, LVN, MS, DSD
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Objectives:
• Name and describe the layers of the skin
• Describe the subcutaneous tissue
• Give the location and function of the accessory structures of the skin
• List the principal functions of the skin
• Summarize the information gained by observation of the skin
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
The Integumentary SystemThe Integumentary System
Skin and associated structures form integumentary system
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Structure of the SkinStructure of the Skin
Skin consists of two layers• Epidermis
• Strata• Dermis
• Blood vessels, nerve endings, and glands
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Cross section of the skin.
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Epidermis
Surface portion of the skin• Stratum basale or stratum germinativum• Stratum corneum
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Dermis
Contains most of the accessory structures of the skin• Blood vessels• Nerves• Sweat glands• Oil glands• Hair• Dermal papillae
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-1: The skin and all its associated structures comprise a body system. What is the name of this system?Checkpoint 6-2: The skin itself is composed of two layers. Moving from the superficial to the deeper layer, what are the names of these two layers?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Subcutaneous Layer
Connects the skin to the surface muscles• Loose connective tissue• Adipose (fat) tissue• Blood vessels• Nerves and nerve endings
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-3: What is the composition of the subcutaneous layer?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Accessory Structures Accessory Structures of the Skinof the Skin
Some structures of the integumentary system protect the skin and have some more generalized functions as well
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Sebaceous (Oil) Glands
Produce a variety of secretions• Sebum• Vernix caseosa• Eye lubrication
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Sudoriferous (Sweat) Glands
Located in the dermis and subcutaneous tissue• Eccrine type sweat glands• Apocrine sweat glands• Ceruminous glands• Ciliary glands• Mammary glands
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-4: Some skin glands produce an oily secretion called sebum. What is the name of these glands?
Checkpoint 6-5: What is the scientific name for the sweat glands?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Hair
Composed mainly of keratin and is not living• Hair follicles• Melanocytes• Arrector pili
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Portion of skin showing associated glands and hair.ZOOMING IN • How do the sebaceous glands and apocrine sweat glands secrete to the outside? What kind of epithelium makes up the sweat glands?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-6: Each hair develops within a sheath. What is this sheath called?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Nails
Made of keratin produced by cells that originate in the outer layer of the epidermis• Nail root• Nail plate• Nail bed• Lunula• Cuticle
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Nail structure.
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Functions of the SkinFunctions of the Skin
Four major functions• Protection against infection• Protection against dehydration (drying)• Regulation of body temperature• Collection of sensory information
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Protection Against Infection
Intact skin forms a primary barrier against invasion• Interlocking pattern resists penetration• Shedding removes pathogens• Protects against bacterial toxins• Protects against some harmful environmental
chemicals
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Protection Against Dehydration
Skin prevents water loss by evaporation• Keratin in the epidermis• Sebum release from the sebaceous glands
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Regulation of Body Temperature
Loss of excess heat and protection from cold are important functions of the skin• Constriction of blood vessels• Dilation of blood vessels• Evaporation of perspiration
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Collection of Sensory Information
Skin has many nerve endings and other special receptors• Free nerve endings• Touch receptors• Deep pressure receptors
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Other Activities of the Skin
• Absorption of substances such as medications• Excretion
• Water• Electrolytes• Wastes
• Manufacture of Vitamin D
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-7: What two mechanisms are used to regulate temperature through the skin?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Observation of the SkinObservation of the Skin
Skin attributes can indicate a serious systemic disorder
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Color
Factors that influence skin color• Amount of pigment in the epidermis
• Melanin• Carotene
• Discoloration• Blood in surface blood vessels• Oxygen in blood• Hemoglobin in blood• Other chemicals in blood
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-8: What are some pigments that impart color to the skin?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Lesions
Any wound or local damage to tissue• Surface lesions
• Macule• Papule• Vesicle• Pustule
• Deeper lesions• Excoriation• Laceration• Ulcer• Fissure
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-9: What is a lesion?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Burns
Categorized by • Depth of damage
• Superficial partial-thickness• Deep partial-thickness• Full-thickness
• Amount of body surface area (BSA) involved• Rule of nines• Lund and Browder method
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Tissue RepairTissue Repair
Wound healing • Occurs only in areas with actively dividing cells
• Epithelial tissues• Connective tissues• Minimally in muscle and nervous tissue
• Is affected by• Nutrition• Blood supply• Infection• Age
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-10: What two categories of tissues repair themselves most easily?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Effects of Aging on the Effects of Aging on the Integumentary SystemIntegumentary System
Changes in• Skin• Tissues• Pigment • Hair • Sweat glands • Circulation • Fingernails and toenails
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Care of the SkinCare of the Skin
• Proper nutrition• Adequate circulation• Regular cleansing
• Removes dirt and dead skin• Sustains slightly acid environment to inhibit
bacteria• Protection from sunlight
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Skin DisordersSkin Disorders
Range from superficial to deep-seated
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Dermatitis
• Inflammation of the skin• Dermatosis is any skin disease
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Psoriasis
• Chronic, recurrent overgrowth of epidermis• Sharply outlined red (erythematous) areas• Flat areas (plaques) covered with silvery scales• A hereditary pattern sometimes present• Immune disorder may be involved
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-11: What is the difference between dermatosis and dermatitis?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Cancer
Skin cancer is most common form of cancer in the United States• Basal cell carcinoma• Squamous cell carcinoma• Melanoma
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-12: What is the name for a cancer of the skin’s pigment-producing cells?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Acne and Other Skin Infections
• Acne• Sebaceous glands disease
• Impetigo• Staphylococcal or streptococcal origin
• Viral infections• Herpes simplex virus• Herpes zoster virus (shingles)• Human papillomavirus (HPV) (wart or verruca)
• Fungal infections• Tinea or ringworm
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-13: What are some viruses that affect the skin?Checkpoint 6-14: What causes tinea or ringworm infections?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Alopecia (Baldness)
Factors that affect baldness• Heredity, aging, and male sex hormones (male pattern
baldness)• Systemic disease• Drugs
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Allergy and Other Immune Disorders
Often involve the skin• Allergy—reaction to a substance• Autoimmune disorders—reaction to one’s own tissues
• Pemphigus• Lupus erythematosus• Scleroderma
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Pressure Ulcers
Pressure ulcers are skin lesions that appear where the body rests on skin that covers bony projections.
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
Checkpoint 6-15: What are several autoimmune disorders that involve the skin?
Cop
yri
ght
© 2
00
4 L
ipp
inco
tt W
illia
ms
& W
ilkin
s
The skin, like our personalities, have various layers, which perform distinct functions—it makes each person unique, obscure, yet familiar. It identifies each individual, yet under the microscope, our skin remains HUMAN in nature.
--Martin Ponciano =)
Recommended