INTEGUMENTARY SYSTEM CS 9-12 Forensic Anatomy
Jan 18, 2016
INTEGUMENTARY
SYSTEM
CS 9-12 Forensic Anatomy
INTEGUMENTARY SYSTEM
· Skin
· Hair
· Nails
· Associated Structures (vessels, nerves, glands)
FUNCTIONS OF THE INTEGUMENTARY SYSTEM· Protection
· Block out pathogens & debris
· Keeps body from drying out
· Nails protect tips of fingers & toes
· Body Temperature Regulation
· Release excess heat, keep in heat
· Hair prevents heat loss from head
· Excretion
· Sweat contains waste products – urea, salt, etc.
FUNCTIONS OF THE INTEGUMENTARY SYSTEM· Information Gathering
· Contain sensory receptors (nerves)
· Connects the outside environment to the nervous system
· Vitamin D Production
· Vitamin D needed to absorb calcium and phosphorous from the small intestine
· Sunlight needed for chemical reaction to produce Vitamin D
STRUCTURE OF THE SKIN
STRUCTURE OF THE SKIN
· Main layers –
· Epidermis
· Dermis
· Hypodermis – not always considered part of skin
EPIDERMIS
Outer layer of the skin2 layers of epidermis
Out layer of the epidermisLayer you seeMade up of dead skin cells
Inner layer of the epidermisMade up of live cellsStem cellsKeratin
protein, hair and nails are made of keratin
Every 4-6 weeks a new layer of skins replaces the dead cells
EPIDERMIS
Contains melanocytesCells that produce
melanin Melanin protects
skin by absorbing UV rays
Responsible for skin color More melanin
produced, darker skin color
DERMIS
Lies beneath the epidermis
ContainsCollagenBlood vesselsNerve endingsGlandsSensory receptorsSmooth musclesHair follicles
DERMIS
Structures here interact with other system to maintain homeostasis, body temperatureCold- blood vessels contract, bring blood closer
to the bodies core, prevents heat from escapingWarm-blood vessels widen, releasing heat from
the body’s coreSweat glands- produce perspiration (sweat)
Sebaceous glands- produce sebum (oil) to keep skin flexible and waterproof, acidic and kills bacteria on the skin’s surface
HAIR Keratin
makes nails and hairHorns, scales, feathers, quills, etc.
Protects head from heat loss & UV rays In nostrils, ears, around eyes
Protects particles from entering the body Hair follicles – pockets of epidermal cells
that extend into the dermis where hair originatesClose to sebaceous glands to keep hair soft
and flexible
NAILS
Grow from the nail root Protects the tips of fingers and toes Grow on average of 3mm/month Fingernails grow ~3X faster than
toenails
SKIN CANCERSkin cancer is the most common type of cancer
2 out of 5 cancers are skin cancers
Skin Cancer· Cancer – uncontrolled cell growth· Caused by damage to the DNA usually
through chemicals or radiation· Two types
· Benign· Does not spread (encapsulated)
· Malignant· Metastasized (moves) to other parts of
the body
Skin Cancer Types
Basal cell carcinoma· Not malignant · Most common type·cannot produce keratin·Boundary lost between dermis and epidermis· Seldom metastasizes – treated surgically or by radiation
· Pale marks· Reddish patches· Round, smooth growth with raised edge· Shiny bumps· Sores that don’t heal
BASAL CELL CARCINOMA
BASAL CELL CARCINOMA
Skin Cancer Types· Squamous cell carcinoma
· 2nd most common skin cancer· Highest risk – fair skin, light hair, blue/green
eyes· Metastasizes to lymph nodes if left untreated
· 1500-2000 deaths in US per year· Early removal allows a good chance of cure· Signs are same as basal cell carcinoma
SQUAMOUS CELL CARCINOMA
MELANOMAS
Malignant Melanoma tends to occur in younger ages (as well as older people)
It is due to repetitive intense exposures (aka: sunburns)
This is the most serious form of skin cancer and MUST be caught early to be treated successfully!
ABCD Rule· A = Asymmetry
· Two sides of pigmented mole do not match· B = Border irregularity
· Borders of mole are not smooth· C = Color
· Different colors in pigmented area· D = Diameter
· Spot is larger then 6 mm in diameter (pencil eraser)
· Mole starts growing/changing in size
Malignant Melanoma
MELANOMAS
MELANOMAS
PREVENTION Wear sunscreen whenever outside or cover up avoid midday sun between 10-2 and beware of
reflected light higher altitudes - every 1000 ft above sea level,
radiation increases 4-5 % Be cautious about tanning beds Medications - tetracycline (antibiotics), Retin A,
birth control, antidepressants, diuretics, and anti-inflammatories cause
photosensitivity avoid sunburns examine skin regularly - remember ABCD
rule – have full body check by dermatologist once a year
OTHER INTEGUMENTARY SYSTEM DISORDERS
· Ezcema· Exposure to allergen/irritant (ie. poison ivy) cause allergic reaction
· inflammation, red, itchy skin· not contagious· over the counter meds; sometimes Rx· Prevention by avoiding allergen/irritant
· Blisters· Epidermal cell injury or separation of epidermis from dermis
· Warts· Contagious· Remove by freezing, drying, laser therapy,
chemicals· Boils
· infection that infects hair follicles· Large, inflamed, pus-filled lesions
TineaFungal infections (ringworm, jock itch, athlete’s foot)Reddish discoloration, scaling, crustingTreat with antifungal agentPrevent recurrence by keeping skin dry
ImpetigoCaused by bacterial infectionMostly childrenReddish discoloration turns into blisters
and yellowish crustsIf turns systemic, it is life threatening
PsoriasisCause is unknown, probably geneticTriggered by trauma, infection, stress
Cutaneous inflammation, scaly lesions Due to excessive rate of epithelial cell growth
UrticariaHivesRaised, red lesions caused by blood vessel leakageSevere itchingCauses (hypersensitivity, allergic reactions, physical irritants, systemic disease)
SclerodermaAutoimmuneAffects blood vessels and CTHard skin lesionsMore common in women
Decubitus ulcers“bedsores” / pressure soresLack of blood flow causes tissue damage
Acne * Clogged sebaceous follicles from abnormal shedding of skin
cells * Bacteria build-up in sebaceous glands * Enhanced by hormones * Over the counter meds; sometimes Rx * Prevention
-avoid using oils, greasy moisturizers, facewash, and makeup
-wash hands before applying makeup-use non-scented ordinary mild soap-keep hands away from face