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The Skin in Health & The Skin in Health & DiseaseDisease

Chapter 6Chapter 6

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The Integumentary SystemThe Integumentary System

Is formed by the skin and its Is formed by the skin and its APPENDAGESAPPENDAGES

Appendages include:Appendages include:– HairHair– NailsNails– GlandsGlands

****CutaneousCutaneous – also refers to the skin – also refers to the skin

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The Structure of the SkinThe Structure of the Skin

Two LayersTwo Layers

– EPIDERMISEPIDERMIS – the outermost portion – the outermost portion

– DERMISDERMIS – contains blood vessels, nerve – contains blood vessels, nerve endings & glandsendings & glands

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EPIDERMISEPIDERMIS

Surface layer of skinSurface layer of skin

Contains Contains MELANIN MELANIN which is the dark which is the dark pigment that colors the skinpigment that colors the skin

FRECKLES FRECKLES are irregular patches of are irregular patches of melaninmelanin

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DERMISDERMIS Extremely elastic, can stretch (as in Extremely elastic, can stretch (as in

pregnancy) with little or no damagepregnancy) with little or no damage Well supplied with blood vessels & Well supplied with blood vessels &

nervesnerves Thickness varies – EX: soles of feet or Thickness varies – EX: soles of feet or

palm of hand (thick layers) & eyelids palm of hand (thick layers) & eyelids (thin, delicate layers)(thin, delicate layers)

Superficial FasciaSuperficial Fascia – connects skin to – connects skin to surface muscles; located directly under surface muscles; located directly under the dermis; blood vessels that supply the dermis; blood vessels that supply the skin & regulate body temperature the skin & regulate body temperature run through the superficial fasciarun through the superficial fascia

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Appendages of the SkinAppendages of the SkinSweat GlandsSweat Glands Coiled, tube-like Coiled, tube-like

structures located in structures located in the dermis & the dermis & subcutaneous tissue subcutaneous tissue (superficial fascia)(superficial fascia)

Regulate body temp Regulate body temp thru evaporation of thru evaporation of sweatsweat

Sweat consists of Sweat consists of H2O, small amounts H2O, small amounts of minerals & other of minerals & other wasteswastes

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Sebaceous GlandsSebaceous Glands Sac-like Sac-like

structures that structures that secrete oils to secrete oils to lubricate skin & lubricate skin & hairhair

Infected glands Infected glands cause pimples!cause pimples!

Blocked glands Blocked glands cause larger cause larger growths called growths called SEBACEOUS SEBACEOUS CYSTSCYSTS

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HairHair Composed Composed

mainly of mainly of KERATINKERATIN (protein) (protein) which thicken which thicken & protect skin& protect skin

Develop Develop within a within a sheath called sheath called a a FOLLICLEFOLLICLE

New hair New hair forms from forms from cells at the cells at the bottom of the bottom of the folliclefollicle

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NailsNails

Protective structures made from hard Protective structures made from hard keratinkeratin

New cells form continuously at the New cells form continuously at the PROXIMAL ENDPROXIMAL END of the nail called the of the nail called the

NAIL ROOTNAIL ROOT

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Functions of the SkinFunctions of the Skin

1.1. Protection against infectionProtection against infection

a)a) Surface cells shed to remove Surface cells shed to remove pathogenspathogens

b)b) Rupture of the outermost layer of the Rupture of the outermost layer of the epidermis (burns or wounds) would epidermis (burns or wounds) would invite infectioninvite infection

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2.2. Protection against DehydrationProtection against Dehydration

a)a) The epidermis is vital in maintaining The epidermis is vital in maintaining homeostasishomeostasis

3.3. Regulation of Body TemperatureRegulation of Body Temperature

a)a) Protects us from the loss of excess heat Protects us from the loss of excess heat & cold temperatures& cold temperatures

b)b) Sweat glands cool the body by drawing Sweat glands cool the body by drawing heat outheat out

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4.4. Collection of sensory informationCollection of sensory information

a)a) Chief sensory organ of the bodyChief sensory organ of the body

b)b) Works with the brain and spinal Works with the brain and spinal cord to sense pain, heat, cold, cord to sense pain, heat, cold, etc.etc.

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What can the skin tell us through What can the skin tell us through observation?observation?

1.1. COLORCOLOR

a)a) Pigment called Pigment called MELANINMELANIN protects protects against UV radiation from the sunagainst UV radiation from the sun

b)b) An increase in melanin will darken An increase in melanin will darken the skinthe skin

c)c) Abnormal increases in melanin may Abnormal increases in melanin may be characteristic of certain be characteristic of certain endocrine disordersendocrine disorders

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d)d) PALLORPALLOR (paleness) – is caused by (paleness) – is caused by reduced blood flowreduced blood flow

e)e) FLUSHINGFLUSHING (redness) – is caused by, or (redness) – is caused by, or often related to, a feveroften related to, a fever

f)f) JAUNDICEJAUNDICE (yellowness) – is often (yellowness) – is often associated with an increase in bile associated with an increase in bile called called BILIRUBINBILIRUBIN. Causes include: . Causes include: HEPATITISHEPATITIS (liver disease) or (liver disease) or STONESSTONES within a bile duct, blocking the flow of within a bile duct, blocking the flow of bile.bile.

g)g) CAROTENEMIACAROTENEMIA – (yellow/orange – (yellow/orange discoloration) – caused by excessive discoloration) – caused by excessive intake of carrots or other deeply intake of carrots or other deeply colored vegetablescolored vegetables

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2.2. LESIONSLESIONS – a wound – a wound to tissueto tissue

Surface LesionsSurface Lesions include: include: RashRash (diaper rash, (diaper rash, measles) &measles) &

EruptionEruption (raised lesion, (raised lesion, such as small pox) such as small pox)

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Deep LesionsDeep Lesions

LacerationsLacerations – jagged – jagged wound caused by wound caused by tearing of the skintearing of the skin

UlcersUlcers – sore – sore associated with associated with disintegration or disintegration or death of tissuedeath of tissue

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FissuresFissures

Cracks in the Cracks in the skin as seen skin as seen in athlete’s in athlete’s footfoot

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Effects of Aging on the SkinEffects of Aging on the Skin

Wrinkles – due to a loss of fat & Wrinkles – due to a loss of fat & collagencollagen

Dermis becomes thinner – skin loses Dermis becomes thinner – skin loses elasticityelasticity

Pigment decreases – hair becomes Pigment decreases – hair becomes grey or whitegrey or white

Hair does not replace itself as rapidly Hair does not replace itself as rapidly & becomes thinner& becomes thinner

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Sweat glands decrease in number Sweat glands decrease in number causing less output of perspiration & causing less output of perspiration & lower ability to withstand heatlower ability to withstand heat

Sensitivity to cold because of poor Sensitivity to cold because of poor circulationcirculation

Dryness, brittleness, flaking and/or Dryness, brittleness, flaking and/or discoloration of hair, skin & fingernails discoloration of hair, skin & fingernails

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Care of the SkinCare of the Skin

Proper nutrition and adequate Proper nutrition and adequate circulationcirculation

Regular cleansingRegular cleansing

Appropriate application of sunscreenAppropriate application of sunscreen

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Skin DisordersSkin Disorders

DermatitisDermatitis – is a general term for an – is a general term for an inflammation of the skininflammation of the skin

– Causes may include:Causes may include:

– Poison Oak/Poison Ivy Poison Oak/Poison Ivy – Allergies to detergents/chemicalsAllergies to detergents/chemicals

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Atopic Dermatitis (Eczema)Atopic Dermatitis (Eczema)

Characterized by Characterized by intense itching and intense itching and skin inflammationskin inflammation

Can include:Can include:– RednessRedness– BlistersBlisters– LesionsLesions– ScalingScaling

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SunburnSunburn

Can cause severe Can cause severe burns, blisters & burns, blisters & swellingswelling

Excessive exposure Excessive exposure is a risk in skin is a risk in skin cancercancer

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MelanomaMelanoma

The fastest The fastest growing form growing form of cancer in of cancer in the United the United StatesStates

Pay attention Pay attention to the to the “ABCD” “ABCD” danger signs danger signs

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ACNEACNE A disease of the A disease of the

sebaceous (oil) sebaceous (oil) glandsglands

Most severe at Most severe at adolescenceadolescence

Some acne can be Some acne can be extremely severe & extremely severe & leave deep leave deep scarringscarring

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ImpetigoImpetigo

An acute, An acute, contagious disease contagious disease of STAPH or STREP of STAPH or STREP originorigin

Can be serious Can be serious enough to cause enough to cause death in an infantdeath in an infant

Blister-like lesionsBlister-like lesions Found frequently Found frequently

among the pooramong the poor

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Alopecia (Baldness)Alopecia (Baldness) Most common Most common

type is “Male-type is “Male-Pattern Baldness”Pattern Baldness”

Can happen to Can happen to men & womenmen & women

Causes include:Causes include:– AgeAge– HeredityHeredity– DiabetesDiabetes– Thyroid diseaseThyroid disease– MalnutritionMalnutrition

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Athlete’s FootAthlete’s Foot

Fungal disease Fungal disease caused by caused by excessive excessive perspiration and perspiration and fungal bacteriafungal bacteria

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PsoriasisPsoriasis

Appears as a Appears as a sharply outlined, sharply outlined, red, flat area red, flat area covered with covered with silvery scalessilvery scales

Cause: Cause: UNKNOWNUNKNOWN

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HerpesHerpes

Appear as cold Appear as cold sores or fever sores or fever blisters on the blisters on the skin & mucous skin & mucous membranes – membranes – including the including the genital areagenital area

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ShinglesShingles

Caused by the Caused by the chicken pox viruschicken pox virus

Affects adults Affects adults causing lesions on causing lesions on the skinthe skin

Pain, itching & Pain, itching & sensitivity can last sensitivity can last more than a yearmore than a year