Integumentary Integumentary System & Body System & Body

MembranesMembranesEQ: How does the structure of EQ: How does the structure of

the integumentary system relate the integumentary system relate to its functional role in protecting to its functional role in protecting

the body & maintaining the body & maintaining homeostasis?homeostasis?

GPSGPS

• SAP2. Students will analyze the SAP2. Students will analyze the interdependence of the interdependence of the integumentary, skeletal, and integumentary, skeletal, and muscular systems as these relate to muscular systems as these relate to the protection, support and the protection, support and movement of the human body.movement of the human body.

• a. Relate the structure of the a. Relate the structure of the integumentary system to its functional integumentary system to its functional role in protecting the body and role in protecting the body and maintaining homeostasis.maintaining homeostasis.

Body MembranesBody Membranes• Function of body membranesFunction of body membranes

– Cover body surfaces: epithelial tissueCover body surfaces: epithelial tissue– Line body cavities: epithelial tissueLine body cavities: epithelial tissue– Form protective sheets around organs: Form protective sheets around organs:

connective tissueconnective tissue

Classification of Body Classification of Body MembranesMembranes

• Epithelial membranesEpithelial membranes– Cutaneous membranesCutaneous membranes– Mucous membranesMucous membranes– Serous membranesSerous membranes

• Connective tissue membranesConnective tissue membranes– Synovial membranesSynovial membranes

Cutaneous MembraneCutaneous Membrane• Cutaneous membrane Cutaneous membrane

= skin= skin– Dry membraneDry membrane– Outermost protective Outermost protective

boundaryboundary

• Superficial epidermis Superficial epidermis is composed of is composed of keratinized stratified keratinized stratified squamous epitheliumsquamous epithelium

• Underlying dermis is Underlying dermis is mostly mostly dense dense connective tissueconnective tissue

Mucous MembranesMucous Membranes• Surface epithelium type Surface epithelium type

depends on sitedepends on site– Stratified squamous Stratified squamous

epithelium (mouth, epithelium (mouth, esophagus, vagina, anus, esophagus, vagina, anus, nose, ears, eyes)nose, ears, eyes)

– Simple columnar Simple columnar epithelium (rest of digestive epithelium (rest of digestive tract, upper respiratory tract, upper respiratory tact)tact)

• Underlying loose connective Underlying loose connective tissue (AKA: lamina propria)tissue (AKA: lamina propria)

• Lines all body cavities that Lines all body cavities that open to the exterior body open to the exterior body surfacesurface

• Often adapted for Often adapted for absorption or secretionabsorption or secretion

Serous MembranesSerous Membranes• Surface- Surface- simple squamous simple squamous

epitheliumepithelium• Underlying layer-thin layer Underlying layer-thin layer

of of areolar connective tissueareolar connective tissue• Lines open body cavities Lines open body cavities

that are closed to the that are closed to the exterior of the bodyexterior of the body

• Serous membranes- Serous membranes- 2 2 layerslayers separated by serous separated by serous fluid-fluid-– 1. 1. Visceral layerVisceral layer ( inner ( inner

layer) covers the outside layer) covers the outside of the organ.of the organ.

– 2. 2. Parietal layerParietal layer (outer (outer layer) lines a portion of layer) lines a portion of the wall of ventral body the wall of ventral body cavity.cavity.

Serous MembranesSerous Membranes• Specific serous Specific serous

membranesmembranes– Peritoneum Peritoneum

(parietal & visceral)(parietal & visceral)• Abdominal cavityAbdominal cavity

– Pleura (parietal & Pleura (parietal & visceral)visceral)• Around the lungsAround the lungs

– Pericardium Pericardium (parietal & visceral)(parietal & visceral)• Around the heartAround the heart

Connective Tissue Connective Tissue MembraneMembrane

• Synovial membraneSynovial membrane– Connective tissue Connective tissue

onlyonly– Lines fibrous Lines fibrous

capsules capsules surrounding jointssurrounding joints

– Secretes a Secretes a lubricating fluid lubricating fluid called called synovial fluidsynovial fluid (which may become (which may become inflamed/ infected)inflamed/ infected)

Integumentary SystemIntegumentary System• Skin (cutaneous Skin (cutaneous

membrane)membrane)• Skin derivatives Skin derivatives

(accessory organs/ (accessory organs/ appendages)appendages)– Sweat glands Sweat glands

(sudoriferous glands)(sudoriferous glands)– Oil glands (sebaceous Oil glands (sebaceous

glands)glands)– Ear glands (ceruminous Ear glands (ceruminous

glands)glands)– HairHair– NailsNails

FunctionsFunctions

• 1. Protection from:1. Protection from:– physical/mechanical physical/mechanical

injuryinjury– pathogen entrypathogen entry– Chemical prevention Chemical prevention

of pathogen entry-of pathogen entry-acid pHacid pH

– UV radiationUV radiation– Drying out/ Drying out/

dessicationdessication

• 2. Sensation2. Sensation• 3. Thermoregulation3. Thermoregulation

• 4. Metabolic 4. Metabolic functions- Aids in functions- Aids in excretion of waste- excretion of waste- urea/ uric acidurea/ uric acid

• 5. Make vitamin D5. Make vitamin D

2 main Skin Layers2 main Skin Layers

1.1. Epidermis- top Epidermis- top layerlayer

2.2. Dermis- middleDermis- middle

3.3. Hypodermis Hypodermis (Subcutaneous (Subcutaneous Layer Layer (SubQ/SQ))- not a (SubQ/SQ))- not a real part of skin; real part of skin; layer of fat.layer of fat.

Skin LayersSkin Layers1.1. Epidermis—outer/ Epidermis—outer/

superficial layersuperficial layer– Stratified squamous Stratified squamous

epitheliumepithelium– keratinized (hardened by keratinized (hardened by

keratinkeratin protein) protein)– .07-.12 mm thick/ 4-5 cell .07-.12 mm thick/ 4-5 cell

layerslayers– avascularavascular

• 4 main cell types4 main cell types::– KeratinocytesKeratinocytes-make -make

keratinkeratin, a protein , a protein which replaces cell which replaces cell contents and protects contents and protects skin skin (Structure)(Structure)

– Merkel Cells-Merkel Cells- (nerve (nerve cells/ sensation)cells/ sensation)

– MelanocytesMelanocytes—produce —produce melaninmelanin, a black brown , a black brown pigment which protects pigment which protects us against UV light us against UV light (pigment)(pigment)

– Langerhans cellsLangerhans cells — —respond to microbes respond to microbes (immunity)(immunity)

Skin LayersSkin Layers

2. Dermis2. Dermis– Dense fibrous CTDense fibrous CT– Some areolar CTSome areolar CT– Highly Highly

vascularizedvascularized– Contain all the Contain all the

skin accessory skin accessory structuresstructures

– 2 layers (papillary 2 layers (papillary & reticular)& reticular)

Skin StructureSkin Structure3. Subcutaneous tissue (hypodermis) 3. Subcutaneous tissue (hypodermis)

is deep to dermis (Not real part of is deep to dermis (Not real part of the skin)the skin)

– Made up of lipids/ fats- “fatty layer”Made up of lipids/ fats- “fatty layer”– Anchors skin to underlying organsAnchors skin to underlying organs– What type of connective tissue is this?What type of connective tissue is this?– What role/ function do you think this What role/ function do you think this

layer serve?layer serve?

Layers of the EpidermisLayers of the Epidermis1.1. Stratum basale Stratum basale

(stratum (stratum germinativum)germinativum)

– Deepest layer Deepest layer – Attached to dermis via Attached to dermis via

basement membrane.basement membrane.– highly mitotic w/ rapid highly mitotic w/ rapid

regeneration rateregeneration rate– Daughter cells are Daughter cells are

pushed upward to pushed upward to become the next layer become the next layer above it (more above it (more superficial layers)superficial layers)

Layers of the EpidermisLayers of the Epidermis2. Stratum spinosum2. Stratum spinosum• 22ndnd deepest layer deepest layer• 8-10 cell layers thick8-10 cell layers thick• Lower mitotic rateLower mitotic rate• Make keratin as cessl get Make keratin as cessl get

pushed up.pushed up.• AKA: spiny/ prickly layer- AKA: spiny/ prickly layer-

b/c when they beign to b/c when they beign to shrink, the desmosomes shrink, the desmosomes connecting adjacent cells connecting adjacent cells look like spikes.look like spikes.

• Recall: What are Recall: What are desmosomes & what do desmosomes & what do they do?they do?

Do you see the spines?Do you see the spines?

Layers of the EpidermisLayers of the Epidermis

3. Stratum granulosum3. Stratum granulosum• 3-5 cell layers thick3-5 cell layers thick• Cells begin to flatten Cells begin to flatten

& die out.& die out.• Contains keratin & a Contains keratin & a

waterproofing proteinwaterproofing protein• ( if water can’t diffuse ( if water can’t diffuse

upward, how would upward, how would the cells above this the cells above this layer receive layer receive nutrients? What would nutrients? What would happen to them?)happen to them?)

Layers of the EpidermisLayers of the Epidermis4. Stratum lucidum4. Stratum lucidum

– 3-5 cell layers of 3-5 cell layers of flat, dead flat, dead keratinocyteskeratinocytes

– Formed from dead Formed from dead cells of the deeper cells of the deeper strata (layer)strata (layer)

– Occurs only in thick, Occurs only in thick, hairless skin of the hairless skin of the palmspalms of hands and of hands and solessoles of feet of feet

– Gives palms/ soles it Gives palms/ soles it light color.light color.

Layers of the EpidermisLayers of the Epidermis5. Stratum corneum5. Stratum corneum

– 20-30 layers of flat, 20-30 layers of flat, keratinized, dead cells.keratinized, dead cells.

– toplayer of epidermis toplayer of epidermis (most superficial)(most superficial)

– Shingle-like dead cells Shingle-like dead cells are filled with keratin are filled with keratin (tough, protective (tough, protective protein prevents water protein prevents water loss from skin)loss from skin)

– AKA: cornified layerAKA: cornified layer• (What type of tissue (What type of tissue

make up this layer?)make up this layer?)• (Why do you think the (Why do you think the

cells died out the cells died out the farther they move up? farther they move up? How do cells in the How do cells in the epidermis get their epidermis get their nutrients?)nutrients?)

Skin Color

Due to 3 pigments:1. Melanin2. Carotene3. Hemoglobin

Melanin• Pigment (melanin) produced by melanocytes• Melanocytes are mostly in the stratum

basale• Color is yellow to reddish-brown to black• All people have the same # of melanocytes,

individual variation in skin color due to how much & what types of melanin is made.

• Amount of melanin produced depends upon genetics and exposure to sunlight

• Protects DNA from UV damage from sun

CaroteneCarotene

CaroteneCarotene::• yellow- to orange yellow- to orange

pigment in plants; not pigment in plants; not made by humans/ made by humans/ animals.animals.

• (how do you think it (how do you think it gets in our skin & gets in our skin & contribute to color?)contribute to color?)

• When large amts are When large amts are eaten, it can deposit in eaten, it can deposit in the stratum corneum the stratum corneum of thick thin. of thick thin. (Which (Which layer is that)?layer is that)?

• Temporary.Temporary.

Hemoglobin:Hemoglobin:• Pigment produced in Pigment produced in

blood cells that blood cells that transport oxygen.transport oxygen.

• Visible in fair-skinned Visible in fair-skinned individuals when individuals when blood rushes to blood rushes to surface of skin.surface of skin.

DermisDermis• Overall dermis structureOverall dermis structure

– Collagen & elastic fibers located Collagen & elastic fibers located throughout the dermisthroughout the dermis• Collagen fibers give skin its toughnessCollagen fibers give skin its toughness• Elastic fibers give skin elasticityElastic fibers give skin elasticity

– Blood vessels play a role in body Blood vessels play a role in body temperature regulation temperature regulation (HOW?)(HOW?)

Dermis- 2 layersDermis- 2 layers

1.1. Papillary layer (upper Papillary layer (upper 1/5 of dermal region)1/5 of dermal region)

• Projections called Projections called dermal papillae dermal papillae – Some contain capillary Some contain capillary

loopsloops– pain receptors & touch pain receptors & touch

receptorsreceptors– Loose (areolar) CTLoose (areolar) CT– Form ridges of Form ridges of

fingerprintsfingerprints• Lots of blood vessels- Lots of blood vessels-

(constrict in cold, dilate (constrict in cold, dilate in warm weather-WHY?)in warm weather-WHY?)

• Sweat & oil glandsSweat & oil glands• Deep pressure / sensory Deep pressure / sensory

receptorsreceptors

2. Reticular layer (deepest 2. Reticular layer (deepest skin layer- lower 4/5 of skin layer- lower 4/5 of dermis)dermis)

• Dense irregular CTDense irregular CT• (What type of fibers does (What type of fibers does

this layer of CT contain?this layer of CT contain?• What properties will this What properties will this

fiber-type confer to this fiber-type confer to this layer? How does this layer? How does this help the skin?)help the skin?)

• Contain majority of Contain majority of accessory structuresaccessory structures

Dermal Papillae Dermal Papillae Reticular layerReticular layer

Skin StructureSkin Structure

Figure 4.4

Subcutaneous Tissue/ Hypodermis

• A.k.a. the hypodermis or the superficial fascia.

• Deep to the dermis.• Consists of primarily

adipose tissue plus some areolar connective tissue.

• Stores energy, provides insulation & padding.

• Anchors the skin to underlying structures, especially muscles.

• Different distribution btwn the sexes.

Skin Appendages/ Accessory Skin Appendages/ Accessory StructuresStructures• Cutaneous glands are Cutaneous glands are

all exocrine glands all exocrine glands (What does this (What does this means)?means)?

1.1. Sebaceous (oil) Sebaceous (oil) glandsglands

2.2. Sudoriferous Sudoriferous (sweat) glands(sweat) glands

3.3. Ceruminous (ear) Ceruminous (ear) glandsglands

4.4. Hair/ hair folliclesHair/ hair follicles

5.5. NailsNails

1

2

4

Sebaceous (oil) glandsSebaceous (oil) glands

– Produce oily, lipid-richProduce oily, lipid-rich

secretion called secretion called sebumsebum..• Lubricates & softens skinLubricates & softens skin• Prevents brittle hairPrevents brittle hair• Decreases skin permeabilityDecreases skin permeability

to waterto water• Kills bacteria (bactericidal)Kills bacteria (bactericidal)

– Most have ducts that empty into hair follicles; Most have ducts that empty into hair follicles; others open directly onto skin surfaceothers open directly onto skin surface

– Glands are activated at puberty Glands are activated at puberty (How is this (How is this related to acne in teens? Why don’t kids get related to acne in teens? Why don’t kids get acne?)acne?)

– Found everywhere except palms & solesFound everywhere except palms & soles

Appendages of the SkinAppendages of the Skin

Figure 4.6a

The sebaceous gland is indicated by the The sebaceous gland is indicated by the arrow. Note how its duct is unbranched and arrow. Note how its duct is unbranched and how it empties into a hair follicle.how it empties into a hair follicle.

Sudoriferous (sweat) Sudoriferous (sweat) glandsglands

– Produce sweat Produce sweat – Widely distributed in Widely distributed in

skin- except nipples skin- except nipples & part of external & part of external genitalia.genitalia.

– > 2.5 million/person> 2.5 million/person– Two typesTwo types

1.1. EccrineEccrine (Merocrine) (Merocrine) sweat glandssweat glands

2.2. ApocrineApocrine sweat sweat glandsglands– Ducts empty into hair Ducts empty into hair

folliclesfollicles

Sweat and Its FunctionSweat and Its Function• Composition:Composition:

– Mostly waterMostly water– Salts (mostly NaCl) and vitamin C, Salts (mostly NaCl) and vitamin C,

lactic acidlactic acid– Some metabolic waste: urea, uric acid, Some metabolic waste: urea, uric acid,

ammoniaammonia– Fatty acids and proteins (more in Fatty acids and proteins (more in

apocrine)apocrine)• Function:Function:

– Helps dissipate excess heat Helps dissipate excess heat (how does (how does this help maintains homeostasis?)this help maintains homeostasis?)

– Excretes waste productsExcretes waste products

Eccrine sweat glandsEccrine sweat glands• More numerous than More numerous than

apocrine glandsapocrine glands• Prominent on the Prominent on the

palms, soles & foreheadpalms, soles & forehead• Ducts empty in pores Ducts empty in pores

on skin surfaceon skin surface• Major function is to Major function is to

cool the body- cool the body- thermoregulation.thermoregulation.

• Mostly water & salts Mostly water & salts (mainly NaCl)(mainly NaCl)

• Acid pH of 4-6; acid Acid pH of 4-6; acid environment kills environment kills bacteria (i.e. chemical bacteria (i.e. chemical protection)protection)

Apocrine sweat glandsApocrine sweat glands• Located in axillary, pubic, anal Located in axillary, pubic, anal

regions.regions.• Larger & thicker than eccrine Larger & thicker than eccrine

glands.glands.• Ducts empty into hair follicle, not Ducts empty into hair follicle, not

directly through pore.directly through pore.• Contain more Contain more lipids & proteins- lipids & proteins-

when degraded by bacteria a foul, when degraded by bacteria a foul, sometimes musty odor is formed.sometimes musty odor is formed.

• Milky or yellow in color.Milky or yellow in color.• Active during pubertyActive during puberty• Secretes during times of pain, Secretes during times of pain,

stress & sexual activity.stress & sexual activity.• No role in thermoregulation.No role in thermoregulation.• (What causes the yellow stains you (What causes the yellow stains you

sometimes see on t-shirt in the sometimes see on t-shirt in the underarm area?)underarm area?)

• (What causes the musty odor?)(What causes the musty odor?)

Ceruminous glandsCeruminous glands

• Modified apocrine glands in the inner Modified apocrine glands in the inner lining of the external ear canal.lining of the external ear canal.

• Secretes a sticky waxy substance called Secretes a sticky waxy substance called cerumen (earwax)cerumen (earwax). It combines w/ . It combines w/ sebum & dead epidermal cells to form sebum & dead epidermal cells to form a bitter compound that offers a barrier a bitter compound that offers a barrier to entry of the ear.to entry of the ear.

• How does this keeps your How does this keeps your

ear germ-free?ear germ-free?

Appendages of the Appendages of the Skin- HAIRSkin- HAIR

• Hair is a flexible strand made of highly keratinized dead cells.

• The keratin in both hair & nails is hard keratin, a stiffer, more compact version of the soft keratin that dominates the epidermis. It is tougher & its cells do not individually flake off.

• The hair is made by the living hair follicle.• MelanocytesMelanocytes provide pigment for hair provide pigment for hair

color.color.• Found all over except- palms, soles, Found all over except- palms, soles,

nipples, lips.nipples, lips.

HAIRHAIR• The hair consists of 3

concentric regions:1. Medulla the

innermost region consisting of large cells and air spaces.

2. Cortex surrounds the medulla and consists of flattened keratinized cells

3. Cuticle outer layer of flat keratinized cells that overlap like shingles with their free edges pointing upward.

Figure 4.7b

HAIRHAIR

Figure 4.7c

Hair and Hair Follicles

• Hair Follicle: Dermal and Hair Follicle: Dermal and epidermal sheath surround hair epidermal sheath surround hair root.root.

• Wrapped around the bulb of the follicle is a network of sensory nerve endings known as the hair root plexus. Allow the hairs to serve a sensory function.

• Attached to each hair is a bundle of smooth muscle known as an arrector pili muscle. In times of fright or cold, these muscles contract and cause the hair to stand on end – and produces goose bumps.– (Increases airflow in mammals with

significant hair (i.e., not humans) and increases the apparent size of an animal with significant hair. Vestigial function in humans).

HAIRHAIR

Figure 4.7a

Notice the hair shaft, hair follicle, papilla, and the multiple sebaceous glands. Where

is the epidermis?

HAIR HAIR

Figure 4.8

Notice the 3 layers of the hair itself.

NAILSNAILS– Scale-like modifications of the epidermisScale-like modifications of the epidermis

• Heavily keratinized dead (hard keratin) cellsHeavily keratinized dead (hard keratin) cells

– Stratum basale extends beneath the nail bedStratum basale extends beneath the nail bed• Responsible for growthResponsible for growth

– Lack of pigment makes them colorless. Lack of pigment makes them colorless. (What (What protein is lacking)? (Why do nails look pink?)protein is lacking)? (Why do nails look pink?)

– (What structure does the nails correspond to (What structure does the nails correspond to in cow, horses, birds, etc.)?in cow, horses, birds, etc.)?

NAILNAIL• Nail structuresNail structures

1.1. Free edgeFree edge

2.2. Body- is the visible attached portionBody- is the visible attached portion

3.3. Root- embedded in skinRoot- embedded in skin

4.4. Nail folds- skin folds form from Nail folds- skin folds form from overlapping cells.overlapping cells.

5.5. Cuticle- is the proximal nail fold that Cuticle- is the proximal nail fold that projects onto the nail bodyprojects onto the nail body

NAIL

1. Nail bed- extension of the stratum basale beneath the nail.

2. Nail matrix- thicken proximal are of nail bed; causes nail growth.

3. Lunula- “crescent”- thicken, white crescent at base of nail.

Appendages of the SkinAppendages of the Skin

Figure 4.9

Skin Homeostatic Skin Homeostatic ImbalancesImbalances

• Imbalance in homeostasis is often Imbalance in homeostasis is often revealed in the skin. More than 100 revealed in the skin. More than 100 different skin conditions.different skin conditions.– Allergies, bacterial, viral or fungals infection.Allergies, bacterial, viral or fungals infection.– BurnsBurns– cancercancer

• InfectionsInfections– Athlete’s foot (tinea pedis)Athlete’s foot (tinea pedis)

• Caused by fungal infectionCaused by fungal infection– Boils and carbunclesBoils and carbuncles

• Caused by bacterial infectionCaused by bacterial infection– Cold soresCold sores

• Caused by virusCaused by virus

Skin Homeostatic Skin Homeostatic ImbalancesImbalances

• Infections and allergiesInfections and allergies– Contact dermatitisContact dermatitis

• Exposures cause allergic reactionExposures cause allergic reaction

– ImpetigoImpetigo• Caused by bacterial infection (Staph)Caused by bacterial infection (Staph)

– PsoriasisPsoriasis• Cause is unknownCause is unknown• Triggered by trauma, infection, stressTriggered by trauma, infection, stress

Skin Homeostatic Skin Homeostatic ImbalancesImbalances

Figure 4.10

Skin Homeostatic Skin Homeostatic ImbalancesImbalances

• BurnsBurns– Tissue damage and cell death caused by Tissue damage and cell death caused by

heat, electricity, UV radiation, or heat, electricity, UV radiation, or chemicalschemicals

– Associated dangersAssociated dangers• DehydrationDehydration• Electrolyte imbalanceElectrolyte imbalance• Circulatory shockCirculatory shock

Rule of NinesRule of Nines• Way to determine the extent of Way to determine the extent of

burnsburns• Body is divided into 11 areas for Body is divided into 11 areas for

quick estimationquick estimation• Each area represents about 9% of Each area represents about 9% of

total body surface areatotal body surface area

Rule of NinesRule of Nines

Figure 4.11a

Severity of BurnsSeverity of Burns• First-degree burnsFirst-degree burns

– Only epidermis is damagedOnly epidermis is damaged– Skin is red and swollenSkin is red and swollen

• Second-degree burnsSecond-degree burns– Epidermis and upper dermis are damagedEpidermis and upper dermis are damaged– Skin is red with blistersSkin is red with blisters

• Third-degree burnsThird-degree burns– Destroys entire skin layerDestroys entire skin layer– Burn is gray-white or blackBurn is gray-white or black

Severity of BurnsSeverity of Burns

Figure 4.11b

Critical BurnsCritical Burns• Burns are considered critical ifBurns are considered critical if

– Over 25% of body has second-degree Over 25% of body has second-degree burnsburns

– Over 10% of the body has third-degree Over 10% of the body has third-degree burnsburns

– There are third-degree burns of the There are third-degree burns of the face, hands, or feetface, hands, or feet

Skin CancerSkin Cancer• Cancer—abnormal cell massCancer—abnormal cell mass• Classified two waysClassified two ways

– BenignBenign• Does not spread (encapsulated)Does not spread (encapsulated)

– MalignantMalignant• Metastasized (moves) to other parts of the Metastasized (moves) to other parts of the

bodybody

• Skin cancer is the most common Skin cancer is the most common type of cancertype of cancer

Skin Cancer TypesSkin Cancer Types• Basal cell carcinomaBasal cell carcinoma

– Least malignantLeast malignant– Most common typeMost common type– Arises from stratum basaleArises from stratum basale

Skin Cancer TypesSkin Cancer Types

Figure 4.12a

Skin Cancer TypesSkin Cancer Types• Squamous cell carcinomaSquamous cell carcinoma

– Metastasizes to lymph nodes if not Metastasizes to lymph nodes if not removedremoved

– Early removal allows a good chance of Early removal allows a good chance of curecure

– Believed to be sun-inducedBelieved to be sun-induced– Arises from stratum spinosum Arises from stratum spinosum

Skin Cancer TypesSkin Cancer Types

Figure 4.12b

Skin Cancer TypesSkin Cancer Types• Malignant melanomaMalignant melanoma

– Most deadly of skin cancersMost deadly of skin cancers– Cancer of melanocytesCancer of melanocytes– Metastasizes rapidly to lymph and blood Metastasizes rapidly to lymph and blood

vesselsvessels– Detection uses ABCD ruleDetection uses ABCD rule

Skin Cancer TypesSkin Cancer Types

Figure 4.12c

ABCD RuleABCD Rule• A = AsymmetryA = Asymmetry

– Two sides of pigmented mole do not Two sides of pigmented mole do not matchmatch

• B = Border irregularityB = Border irregularity– Borders of mole are not smoothBorders of mole are not smooth

• C = ColorC = Color– Different colors in pigmented areaDifferent colors in pigmented area

• D = DiameterD = Diameter– Spot is larger then 6 mm in diameterSpot is larger then 6 mm in diameter