Integumentary System
Chapter 6
First line of defense
Structure – classified as a membrane
 Epidermis – epithelial layer
 Dermis – vascular connective tissue
 Subcutaneous layer – loose – collagen + adipose
Thin and thick skin
 Most is thin – surface
 Remainder – thick – palms, soles
 Thick – each of the five layers are present
 Dermal papillae creates fingerprint
Cell types of epidermis
 Keratinocytes – most important cells – 90% - principal
structural element
 Melanocytes – black or brown – protection – 5%
 Langerhans cells – immune response – defense – cytopoesis
in marrow – help T-cells (trigger for immune system
response)
Hyperkeratosis
The epidermis contains 5 layers. From
bottom to top the layers are named:
stratum basale
stratum spinosum
stratum granulosum
stratum licidum
stratum corneum
Develop a saying to remember
these layers……..BSGLC
Best one wins!
Epidermis Anatomy - Keratinocyte
Maturation
http://dermatology.about.com/od/anatomy/ss/epi
dermis.htm
Cell Layers
 Stratum corneum – superficial – thin squamous (flat) cells –
dead – cytoplasm replaced with keratin – membranes thick –
prevents dehydration – first line of defense – abnormality
(hyperkeratosis)
Stratum lucidum
 Keratinocytes tightly packed and clear
 No nucleus
 Cells filled with gel-like eleidin which becomes keraatin
 Eleidin blocks fluid penetration
 Absent in thin skin, but present in thick skin
Stratum granulosum
Keritinization
Lipids formed from granules that form waterproof barrier
Stratum spinosum
Spiny layer – latin spinosus
8-10 layers – irregularly shaped cells
Found in epidermal layer and rich in RNA
Protein - producing
Stratum basal
 Single layer
 Deepest stratum
 Continual mitosis
 35 d to surface
The stratum germinativum is composed
of the basale/spinosum together.
This is known as the
growth layer.
Dermis
Dermis
 Thicker than epidermis
 Blood vessels
 Nerves
Papillary layer
 Thin surface of the dermis
 Forms lumpy bumps called dermal papilla
 Loose connective tissue, collagen, and elastin
 Forms ridges
 Well defined on finger tips - griping
 “fingerprinting”
 Allows for griping
Fingerprinting technique:
 Tape
 Pencil
 Paper – two sheets
History of fingerprinting
 Hx. – brand, tattoo, miame criminals
 Levenworth – over 800,000 collected –
early 1900’s
 Currently - >250 mil.
Fingerprinting styles
A central pocket loop.
The double loop.
The plain whorl.
The loop.
A plain arch.
The tented arch.
An accidental print.
*Photos courtesy of
Hillsborough County
Sheriff's Office.
Of Interest
The word forensic
science comes from the
Greek word 'forum',
meaning court of law, so
technically forensic
science is a type of
science that is used in a
court of law.
Case Study
On the morning of the
27th December 1996,
Patsy Ramsey called the
police to report her 5year-old daughter, Jon
Benet Ramsey, missing.
The little girl had
disappeared from her
bedroom...more...
To download Flash
Player:
Reticular layer
 Thick – much more dense in fibrous structure
 Dermis
 Fibrous/collagenous – commercially processed from animals is
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sold as leather
Elastin also present – ability to rebound – abnormal conditions do
exist
Dehydration test – pinch an inch!
An attachment for skeletal/smooth muscles
Expression in face – skeletal
Hair follicle response ( arrector pili/smooth muscles) –goose
flesh, elevation of testicle, erection of nipple – creates heat
Sensory receptors found here – transmission of impulses
Dermal growth/repair
 Dermis can regenerate from fibroblasts that creates a place
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where connective tissue is replaced by normal tissue
If normal tissue fails to fill in a scar is left behind
Langer’s cleavage lines help to hide incisions and have a
better tendency to remain in tact during healing
Elastin can be stretched too much and linear markings
remain – pregnancy – tears in elastin
Also known as strae
Keloid
Color my World!
 Melanocytes - Melanin – brown or black
 Converts amino acid tyrosine into dark pigments
 Depends on genetics, sun exposure, ACTH - pituitary
 Absence – albanism
 Carotene – yellow/orange
 Erythema - vessels
Abnormal changes
 Vitiligo
 Cyanosis
 Jaundice
Vitiligo
Vitiligo
Cyanosis
Erythema
Jaundice
Skin functions:
 Protection
 Sensory perception
 Excretion
 Movement
 Vitamin D production
 Immunity
 Regulation of body temp.
 Production
 Loss
Protection
 Chemicals
 Trauma
 Sun exposure
 Barrier - “surface film”, bacteria/fungus
Sensory perception:
Volunteers?
Sensation
 Sensory organ
 Pressure
 Touch
 Temperature
 Pain
 Vibration
Movement
 Elastin content
 How much is too much?
Or not enough Scleroderma
Excretion
 Sweat – from what gland?
 Urea, salt, ammonia, uric acid – waste products of urinary
system and tissue breakdown
VitaminD Production
 UV – A/B
 7-dehdrocholesterol -- colecalciferal
 Transferred to liver/kidneys for conversion
 Purpose –
 Summer? Winter?
Immunity
 T-cells – helps to form proteins to fight against microbes
 Fungus
 Bacteria
Body Temperature regulation
 Circadian Rhythm
 Production – metabolism
 Loss – evaporation, radiation, conduction, convection
Burns
 1st
 2nd
 3rd
 Assessment – Rule of nines/palm
Appendages
Hair
 Growth begins in-utero (lanugo)
 Lost before birth
 Replaced by vellus hair – fine, light in color
 Terminal hair during puberty
 Hair grows from the follicle
 Visible portion – shaft
 Core – medulla
 Outer portion – cortex
 Covering - cuticle
Hair variables
 Brown or black – melanin
 Red – melanin containing iron
 Straight – shaft is round and cylindrical
 Wavy – flat shaft – not as strong
 Sebaceous production – sebum
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Growth – ½ inch per month/ lasts 2-6 years
Male pattern baldness
Alopecia
Rogaine
Nails
 Grows from cuticle
 Lunula – little white moon
 Nail bed – epithelial tissue, blood vessels, nerve endings
 Growth – 0.5mm per week
 Fingernails grow faster than toes
 Growth more rapid in summer
 Onycholysis
Fungal
Pseudomonas - bacterial
Psoriasis
Psoriasis
Glands
 Sudoriferous
 Sebaceous
 Ceruminous
Abnormalities
Infections
 Impetigo - staphylococcus or streptococcus
 Tinea - fungus
 Warts - virus
 Boils - usually staph – furuncle/carbuncle
Vascular/inflammatory conditions
 Decubitus
 Urticaria
 Scleroderma
 Psoriasis
 Eczema
Decubitus Ulcer
E
Eczema
Boil – furuncle/carbuncle
Dermatitis
Scabies
Strep B
Jake – Strep B
Streptococcus B
Drug resistant Strep B
Growths to watch! – Basal cell
Squamous cell
ABCDE’s of melanoma
ABCDE’s of Melanoma
Avoid these previous conditions!
No tanning beds/prolonged sun
exposure
SUNSCREEN-review criteria
No sunburns
Check yourself!
Notice others