Anatomy and physiology of friction ridge skin lecture 1

SKIN IS THE LARGEST ORGAN PART OF THE BODY


Skin functions

Temperature regulation

Insulation and cooling

Protection

External and internal environment

Sensory and sensation

-specialized cells and nerve free endings

Energy source in fat tissue


Skin definion - skin is the largest organ part of the body composed of three layers


3 layers of skin

Epidermis-outermost layer of skin and prevents water loss via evaporation-1st layer

Dermis-middle layer of skin and primarily layer of connective tissues and structural component od nourishment of the dermis 

Hypodermis-inner most layer of skin and consist of loose connective tissue and fat adipose cells and provides energy reserve and structual components


Friction ridge skin

-surface level rooted in the dermis by primary ridges and secondary ridges 


Primary ridges-under the ridges

Secondary ridges-under the furrows


Primary and secondary ridges areinterlocked with the dermis 


Epidermis-what it is

Renewing keratinocytes and exhibits and progressive differentiation at the lowest level and cells pushed toward the surface and further changes in chemical composition


Epidermis-cell differentiation 

Keratinocytes-primary cell of epiderms-90-95 percent of epidermis cells, travels rom basal layer to the surface which undergoes cell differentiation


Keratin

-durable porein when organizing into bundles and providing structural support to cells by extension

Roughly 20 variation


Other key cells included m, l , m

Melanocytes, langerhans, merkel cells


Keratin 

Key cells include

Melanocytes- has pigment of melanin in keratinocytes and protect genetic material\

Langhans-  has extension of the immune system and recruits t cells from the body to attack invaders

merkel - exstention of the nervous system and plays a role in sensation of touch


Layers of epidermis  (5)

Bsglc

Stratum basale-innermost layer of the cell consists of a single layer of keratinocytes,melanocytes and merkel cells

Stratum spinosum-keratinocytes are pushed toward the surface and begin cell differentation

Stratum granulosum - keratinocytes continue structural and chemical modification. Lamellar granules are introduced

Stratum lucidum - keratinocyes continue their programed cell death

Stratum corneum- layers of stacked chemically dead cells

Epidermis - Stratum Spinosum

• Keratinocytes while subjected to differentiation become polyhedral in shape and desmosomes [cell junctions) are reinforced.

Keratin production is increased, and the filaments extend into the desmosomes.


Epidermis - Stratum Granulosum

1 Granulosum - Think: Granules

• Keratinocytes fill with Keratin and lamellar granules release their lipid content.

As the keratinocytes travel up toward the surface - between stratum granulosum and stratum lucidum- the lamellar granules release their lipid content forming a hydrophobic barrier.


Epidermis - Stratum Lucidum &

Stratum Corneum

• Stratum Lucidum (clear, lucid, ghostly) - By this layer, the keratinocytes have completed their programmed cellular death.

Even still, chemical activity is continued.

• Stratum Corneum (corny, hard) - as dead keratinocytes rise to the surface they form a brick-and-mortar structure.

with the Keratin-filled cells being the bricks and the lipids being the mortar.

• As the cells are pushed toward the surface the cell membrane is weaker/ brittle and allows the cells to be sloughed off (which is a feature).



Lets talk dermis  (PR) (2)

Papilary layers- loose connective tissue containing firbirls and dermel cells

Recticular layers0 compacted connective tissue containing collagen and elastic fibers



Dermis- papillae layer (DA) (2)


Dermal papillae- a finger like projection between primary under friction ridge and secondary under furrows


Anastomoses- tissue sheets form from the epiders that cross link near by the primary and secondary ridges forms follow function 

Anastomoses


Attachment between anastomoses and dermal papilae increasing the area between the two of the epiderdims and dermis by the extstneion increasing the bond between the two


Features of the dermis- 

Sensory and automatic nerve branches


-touch,temeprature,pain and itching


Nerve free endings

Meissner  corpuscles (touch)

Ruffini coprscules (pressure)

Pacinian corpuscles (pressure)


Meissner corpscules (touch)

Ruffini corpscules (pressure )

Pacanian corpuscles (pressure)


M r p



Mrp


Messiner corpusles-touch

Ruffini0pressure

Paacian corpsules 


Dermis features

Sensory and automatic 


Temperature, touch, pain, and itching


Mrp

Nerve free endings

Meissner  corpuscles (touch)--transmitting sensations of fine discriminative touch and vibration in dermis

Ruffini corpuscles (pressure)-sensory receptors in the dermis that detect pressure

Pacinian corpuscles (pressure)-sensory receptors in the dermis that respond to deep pressure and vibration



Dermis features sensory and automatic


Temperature,touch pain, itching 


Sweat and temperature 


Sweat is through the pores in the skin  and vzrious areas  and in different amounts

The body is exposed to varying temperature conditions 


Sweat consists of eccrine and sebaceous 


Sweat is through the pores and the skin and in various areas and in different amounts

The body is exposed to varying tempeartue conditions


Sweat is through the pores and skin in various areas in different amounts the body is exposed to varying temperature conditions


Sweat is through the pores and the skin in various areas and in different amounts the body is ecxposed to varying temperature conditiions


Sweat consit of errcine and sebacceous 


Erricne sweat- primarily composed of water salt potassium ammonia urea amino acids,hormones enxymes and vitamins


Sweat is prduced from ericne sweat glands and are the primary appendage of friction ridge skin 


Sweat is produced from erricne sweat glands and are the primary appendage of friction ridge skin 


Sweat is produced from aricne sweat glands and are the primary appendange of friction ridge skin


Sweat is produced from erricne sweat glands are the primary appendafe of friction ridge skin



Sweat is produced from erricne sweat glands are the primary appendage of friction ridge skin 


Sweat is produced from ericne seat glands are the primry appendage of friction ridge skin


Sweat is produced from ericne sweat glands are the primary ppendage of friction skin


Sweat is prodcuced from erictine glands and are the primary appendange of firction ridge skin


Ericne sweat is composed of salt potassium water amino acids hormones enzymes and vitames


Erricne sweat is composed of salt potassium water hormons enzymes amino accid vitamines



Physiology of the firction ridge skin

Physical attachments 

Primary and secondary ridges anastomosis and dermal papilae


Basmement membrane zone-fiborus sheet which attacheds the basal keratinocytes of the epidermis to the underlying dermal  dermis layer


Basmement membrane zone-fibrous sheet attaches the basal keratinoyctes epidermis to the underlying dermal dermis layer


Basement memerane zone-fiborus sheet attaches to the basal keratinocytes eperdmis to the underlying dermis layer


Fiboruos sheet attaches to thebasal kerainotyces eperdimis underlying dermis layer

Fbourus sheet attached to the basal keratinocytes epedermis to the underlying dermis layer


Fiborus sheet attached to the basal kertainocytes epedrimis to the the udnerlying dermis layer


Basememnt bembrane-fiborus sheet attached to the basal keratinocytes eperdmis to the underlying dermis layer 


Cell to cell attachements - desmoses and focal tight junctions


Cell to cell attachements-desmoses and focal tight junctions


Cell to cel attachements-desmoses and focal tight junctions


Basement membrane - fibrous sheet attached to the keratinocytes epidermis to the underlying dermiis layer


Fibrous sheet attached to the keratinocytes epeidermis to the under lying dermis layer


Fiborus sheet attached to the keratinoyctes epeiderm and to the under lying dermis layer 


Cell to cell attachemnts desmoses and focal tight junctions


Cell communication-

Gap junctions these are connections between the cell memebrane of adjancent cells  that permit a direct exchange of small molecules ions and hormones


Gap juctions these are conection between the cell membrane of adjancent cells that permit a direct exchange of small molecules ions and hormones


Gap junctions these are connctions linked to the cell membrane of adjancent cells that permit direct exchange of small molecules ions an dhormones


Gap junction-these are connection linked to the cell membrane of adjnacent cells that permit direct exchhange of small molecues ions andhormones


These are connections linked to the cell membrane of adjancent cells that permit direct exchange of small molecules ions and hormones



These are connections linked to the cell membrane of adjancent cells that permit direct exchange of small molecules ions and hormones


These are connections linked to the cell membrane of adjancent c ells that permit direxct exchange of small ions an dhormones



Cell surface receptions-throughtout the outer membrane there are specific modefied proteins that can respond to signals sent from other cells with epidermis 


Cell surface receptions-throughout the outer membrane tehre are specific modified proteins that can respond to signals sent from other cells with epidermis


Cell surface receptions-throughtout the outer memrane there are specific modified proteins that can respond to signals sent from other cells with epidermis


Throughout theoouter membere there are specific modified proteins that can respond tosignals sent from other cells with epidermis 


Persistence of frs 

Aging of the firction ridge skin happens through one of ttwo ways

The friction ridge flatten

The gradual loss of the eleasicity become flaccid or wrinkled


Presiencetence of frs

Flattening of friction ridges occurs in summary when the dermal papilae  grow and branch out the firction ridge surface ridge become flatten


Flatteniting of friction ridges occurs in the sumary when the dermal papilae grown and branch out


Flattening of friction ridges occurs in the summary when the dermal papiler grown and branch out the friction rdge beocme flatten


Wrinles results are due to when the mechanicla changes in the skin ages the collagen unravels and loose eleascity 


Brekadown in fiber networks result the skin to beocme loose and folds on it self


Wrinkels results are due whenthe mechanical changes int he askin ages and collages unravels and loose elasicity 


Breakdown in fiber networks result the skin to become loose and folds on itself


Presientce of frs-wound healing


Phase one infflamation-occurs as blood cells travels to the cite region to direct the response 

Phase 2 proliteration the basal keratinocytes are exposed to the de2rmis due to theinjurt to hthe basmement membrane 

Proffileration- the basal keratinocytes exposed to the derrmis due to the injurt to the basement membrane


The basal keratinocytes are exposed to the demris due to the injurt to the basememnt of the membrane


The basal keratinocytes are exposerd to the dermis due to the injurt to the basement of the memnbane 


Phase 3-tissue remodiling- the epidermis has been retsored and the dermis continues to reinforce and remodel the skinc fora continuted period of time


The epidermis has restored and the dermis coniunes to reninforde and remodel that skin for a continued period of time


The epidermis has been restored and the dermis contintues to reinfiorce and remodel that skin for a continued period of time 


Persisence of frs


Inflamiation profileration tissue remodilng


Frs follows the thoery of dicriminaiton and persistence