Copyright 2003 by Mosby, Inc. All rights reserved. INTEGUMENTARY SYSTEM

Copyright 2003 by Mosby, Inc. All rights reserved.

INTEGUMENTARY SYSTEM


Structure and Function

• Integumentary system is composed of the skin and accessory structures

• Functions of the integumentary system– Protects the other body systems from

injury and infection– Helps the body maintain homeostasis by

regulating temperature, retaining body fluids, and eliminating wastes


Figure 9-1 Skin Structures


Skin

• The largest organ of the body • Varies in thickness from 1/50 inch (0.5

mm) in the eyelids to 1/4 inch (6.3 mm) in the soles of the feet

• Changes in the skin often indicate the presence of other body system disorders including anemia, respiratory disorders, liver disorders, cancer, and shock

Abnormal Colors of the Skin• Erythema: reddish; burns or blood vessel

congestion• Jaundice: yellowish; liver or gallbladder

disease• Cyanosis: bluish; insufficient oxygen

Layers of Skin

• Epidermis– Outermost layer of the skin that is composed of a

surface of dead cells with an underlying layer of living cells; avascular, no nerves, etc.

• Dermis– Called the “true” skin; the dermis contains the

blood vessels and nerves, connective tissue

• Subcutaneous/ Hypodermis– Fat containing; joins skin to muscle

Copyright 2003 by Mosby, Inc. All rights reserved. Our Skin Video

How many skin cells do we shed daily?

Between 30,000 and 40,000 of them fall off every hour. Over a 24-hour period, you lose almost a million skin cells [source: Boston Globe].Where do they all go? The dust that collects on your tables, TV, windowsills and on those picture frames that are so hard to get clean is made mostly from dead human skin cells. In other words, your house is filled with former bits of yourself. In one year, you'll shed more than 8-10 pounds (3.6 kilograms) of dead skin. It gets even grosser: Your house is also filled with trillions of microscopic life forms called dust mites that eat your old dead skin.

Burn Victim


Hair and Hair Follicles

• Skin has hair in all areas except the soles of the feet and palms of the hands

• Hair serves to block foreign particles from entering the body through structures such as the nose and eyes

• The visible portion is called the shaft • The hair follicle is the root with its

covering

Hair and Hair Follicles

• Hair growth is similar to the epidermal cell growth• Deep lying cells in the root move forward through

the shaft • Melanocytes located at the root give it pigment

(black cells)• Hormone production decreases as we age, therefor

hair turns gray/ transparent

Look up: What muscle aids in goose bumps?

Nails

• Hard keratin plates• Grow approx. 1mm a week• May regrow completely in 3-5 months• Toenails grow slower than fingernails


Glands

• Three types of glands in the skin– Sebaceous glands (oil)– Sudoriferous glands (sweat)– Ceruminous glands (wax)

• Function is to help regulate the body temperature and excrete body wastes

Sebaceous Glands

• Produces oily secretion called sebum• Carried by ducts and secreted through pores• Lubricates the skin• Associated with hair follicles• Influenced by sex hormones

– Over active at puberty (what does this do?)

– Under active at old age (what does this do?)

Sudoriferous Glands

• Coiled glands• Produces sweat

– Helps cool body

– Carried by ducts and excreted through pores

– Almost pure water, less 1% is salt, wastes, etc

– Colorless and odorless

– The odor comes from sweat mixed with bacteria on the skin


Dermis

Hair follicle

Lip/oNecrotic

Cyanotic

Hypodermis

Arrector Pili

SebaceousCutane/o


Adip/o

Aut/o

histologyErythem/o

Cyanotic

Avascular

Sudoriferous

Pil/oSubcutaneous


Disorders/ Conditions of the Integumentary System • Acne vulgaris

– Caused by increased secretion of oil related to increased hormones during puberty

• Albinism – Inherited disorder in which melanin is not produced- eyes are red due to lack of pigment so see blood vessels

• Alopecia– hair loss


Conditions/ Disorders of the Integumentary System (continued)

• Cleft lip or cleft palate– Upper lip has a cleft where the nasal palate doesn’t meet properly

• Contact dermatitis– Allergic reaction that may occur after initial contact or as an acquired response

• Cyst– Small sac or pouch containing fluid or semisolid fluid


• Dandruff– White flakes of dead skin cells from the scalp

• Decubitus ulcers– Bed Sores or areas of inflammation that occur over bony prominences of the body

• Ecchymosis– Bruise, hemorrhaging into the skin

• Eczema– Group of disorders caused by allergic or irritant reactions


• Furuncle– Boil, or bacterial infection of a hair follicle

• Impetigo– Very contagious bacterial skin infection that occurs most often in children

• Kaposi’s sarcoma– Form of cancer that originates in blood vessels and spreads to skin

• Keloid– Thickened scar


• Tinea– Fungal skin infections that live on epidermis

• Athletes foot (pedis)• Ringworm• Jock Itch

• Gangrene– Death of tissue associated with lack of blood supply

• Wheal• hives


• Wart (verruca)– Papule caused by a viral infection

• Psoriasis– Chronic skin disorder in which too many epidermal cells are produced

• Nevus– Mole

• Hemangioma• A cluster of blood vessels that make an abnormal benign

growth/ some are birthmarks

Hemangioma

Nevus

WartTinea Pedis

Psoriasis


Gangrene


Skin Injuries

• Excessive Skin exposure– Sun Types

• Type 1: burns, never tans; fair SPF 30• Type 2: burns, tans min, fair SPF 30/15• Type 3: burns mod, tans grad, SPF 30/15/8• Type 4: burns min, tans well, SPF 30/15/8• Type 5: rarely burns, tans profusely, SPF

15/8• Type 6: never burns, deep pigmented, SPF

8


Skin Injuries

• Burns– 1st Degree- no blisters, mainly

epidermis– 2nd Degree- blisters, epidermis & top

layer of dermis– 3rd Degree- damaging all 3 layers,

necrotic

Skin Cancer

• Carcinoma• Cancerous tumor

– Squamous cell: scalp and lower lip, rises from epidermis– Basal cell: most common, face, starts at epidermis

• Malignant Melanoma– Occurs in melanocytes

• Nevus- mole becomes dark• Death 1:4• Metastatic• Sun or tanning bed


Strangest Medical Conditions Video

Clinical Procedures

• Skin biopsy– Lesion is removed from the skin and sent to

patho lab for tests

• Skin Testing for Allergiesscratch test and intradermal test

• Debridementremoval of dirt, foreign materials

• Incisions & drainageopen a lesion and drain

Clinical Procedures

• Cryotherapy– Destruction of tissue by freezing it with liquid

nitrogen

• ElectrolysisDestruction of tissue by electricity; used to remove

hair• Liposuction

Surgical removal of fat from subcutaneous tissue by suction

• Rhytidectomy(facelift) removal of wrinkles

• Liposuction Video


Documents

Copyright 2003 by Mosby, Inc. All rights reserved. INTEGUMENTARY SYSTEM