Skin AppendagesSkin Appendages

►CutaneousCutaneous (relating to skin) (relating to skin) glandsglands Sebaceous glandsSebaceous glands Sweat glandsSweat glands

►HairHair►Hair folliclesHair follicles►NailsNails

These appendages come from the epidermis and help maintain the body’s homeostasis.

Appendages of the SkinAppendages of the Skin

►Sebaceous glandsSebaceous glands Produce oilProduce oil

► Lubricant for skin which keeps skin soft and Lubricant for skin which keeps skin soft and moistmoist

► Prevents brittle hairPrevents brittle hair► Kills bacteria (slightly acidic)Kills bacteria (slightly acidic)

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 and this is Glands are activated at puberty and this is what causes teenage acnewhat causes teenage acne

Appendages of the SkinAppendages of the Skin

Facial BlemishesFacial Blemishes►WhiteheadWhitehead – –

sebaceous gland is sebaceous gland is blocked usually from blocked usually from the oily substance the oily substance made by the gland.made by the gland.

► BlackheadBlackhead – when – when whitehead dries, it whitehead dries, it darkens forming darkens forming blackheadblackhead

► AcneAcne – an active – an active infection of the infection of the sebaceous glands sebaceous glands caused by bacteriacaused by bacteria

Appendages of the SkinAppendages of the Skin►Sweat glandsSweat glands

Produce sweat Widely distributed in skin Produce sweat Widely distributed in skin (2.5 million per person)(2.5 million per person)

helps cool the bodyhelps cool the body Two typesTwo types

► EccrineEccrine Open via duct to pore on skin surfaceOpen via duct to pore on skin surface Most numerous on the bodyMost numerous on the body

► ApocrineApocrine Ducts empty into hair folliclesDucts empty into hair follicles Found mostly in armpits and genital areasFound mostly in armpits and genital areas Precise function is unknown but are they are Precise function is unknown but are they are

activated during pain, stress and during sexual activated during pain, stress and during sexual foreplay.foreplay.

Appendages of the SkinAppendages of the Skin

Sweat and Sweat and Its FunctionIts Function

►CompositionComposition Mostly waterMostly water Salts and vitamin CSalts and vitamin C Some metabolic waste (urea and uric acid)Some metabolic waste (urea and uric acid) Fatty acids and proteins (apocrine only)Fatty acids and proteins (apocrine only)

►FunctionFunction Helps rid body of excess heatHelps rid body of excess heat Excretes waste productsExcretes waste products Acidic nature inhibits bacteria growthAcidic nature inhibits bacteria growth

►Odor is from associated bacteriaOdor is from associated bacteria

Appendages of the SkinAppendages of the Skin

►HairHair Produced by hair Produced by hair

follicle which are follicle which are made of hard made of hard keratinized keratinized epithelial cellsepithelial cells

MelanocytesMelanocytes provide pigment provide pigment for hair colorfor hair color

Structure of Hair FollicleStructure of Hair Follicle

Hair AnatomyHair Anatomy►Hair anatomyHair anatomy

Central medullaCentral medulla CortexCortex surrounds surrounds

medullamedulla CuticleCuticle on outside of on outside of

cortexcortex► Most heavily keratinizedMost heavily keratinized

Hair StructuresHair Structures

►Associated hair structures Associated hair structures Hair follicleHair follicle

► Dermal and epidermal Dermal and epidermal sheath surround hair rootsheath surround hair root

Arrector pili muscleArrector pili muscle ► Smooth muscleSmooth muscle► Pulls hairs upright when cold Pulls hairs upright when cold

or frightenedor frightened

Sebaceous glandSebaceous gland

NailsNails

►NailsNails Scale-like modifications of the Scale-like modifications of the

epidermisepidermis►Heavily Heavily keratinizedkeratinized

Stratum basaleStratum basale extends beneath the extends beneath the nail bednail bed► Responsible for growthResponsible for growth

Lack of pigment makes them colorlessLack of pigment makes them colorless

Nail AnatomyNail Anatomy►Nail structuresNail structures

Free edgeFree edge Body is the visible attached portionBody is the visible attached portion Root of nail embedded in skinRoot of nail embedded in skin Cuticle is the proximal nail fold that projects onto Cuticle is the proximal nail fold that projects onto

the nail bodythe nail body

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 (worst) (worst) Destroys entire skin layerDestroys entire skin layer Burn is gray-white or blackBurn is gray-white or black

Severity of BurnsSeverity of Burns

Rule of NinesRule of Nines

►Way to determine the extent of burnsWay to determine the extent of burns►Body is divided into 11 areas for quick Body is divided into 11 areas for quick

estimationestimation►Each area represents about 9% of total Each area represents about 9% of total

body surface areabody surface area

Rule of NinesRule of Nines

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