© 2015 pearson education, inc. figure 5-1 the components of the integumentary system. epidermis...

© 2015 Pearson Education, Inc.

Figure 5-1 The Components of the Integumentary System.

Epidermis

Cutaneous Membrane

Papillary layer

Reticular layer

Dermis

Hypodermis

Hair shaft

Pore of sweatgland duct

Tactile (Meissner’s)corpuscle

Sebaceous gland

Arrector pili muscle

Sweat gland duct

Hair follicle

Lamellated (pacinian) corpuscle

Nerve fibers

Sweat gland

Artery

VeinCutaneous plexus

Fat

Accessory Structures

p. 151


Figure 5-2 The Cutaneous Membrane and Accessory Structures.

Integumentary System

Cutaneous Membrane Accessory Structures

Epidermis Dermis

Papillary Layer Reticular Layer

Hair Follicles Exocrine Glands Nails

FUNCTIONS

Protects the dermis,prevents water loss andthe entry of pathogens,and synthesizes vitaminD3. Sensory receptors

detect touch, pressure,pain, and temperature

Nourishes andsupports epidermis

Has sensory receptors

that detect touch,

pressure, pain, vibration,

and temperature. Blood

vessels assist in

thermoregulation

Hairs protectskull and providedelicate touchsensations ongeneral bodysurface

Assist intemperatureregulation andwasteexcretion

Protect andsupport tipsof fingersand toes

• Physical protection fromenvironmental hazards

• Storage of lipids

• Coordination of immuneresponse to pathogensand cancers in skin

• Sensory information• Synthesis of vitamin D3

• Excretion• Thermoregulation

p. 152

The structural relationship andinterface between the epidermisand underlying dermis. Theproportions of the various layersdiffer with the location sampled.

Dermis

Epidermis

Epidermalridge

Dermalpapilla


p. 154

Figure 5-2b The Basic Organization of the Epidermis

A micrograph ofthin skin, which covers most ofthe exposedbody surface.

Stratumcorneum

Basementmembrane

Dermis

Thin skin LM 154


p. 154

Figure 5-3 The Epidermis (Part 2 of 3).

Surface

Basementmembrane

Stratumcorneum

Stratumlucidum

Dermalpapilla

Epidermalridge Thick skin LM × 200

Epidermis

Stratum corneum

Characteristics

Dermis

Stratum lucidum

Stratum granulosum

Stratum spinosum

Stratum basale

• Multiple layers of flattened, dead,interlocking keratinocytes

• Water resistant but not waterproof• Permits slow water loss by insensible

perspiration

• Appears as a glassy layer in thick skinonly

• Keratinocytes produce keratohyalin andkeratin

• Keratin fibers develop as cells becomethinner and flatter

• Gradually the plasma membranes thicken,the organelles disintegrate, and the cells die

• Keratinocytes are bound together bydesmosomes

• Deepest, basal layer• Attachment to basement membrane• Contains basal cells (stem cells),

melanocytes, and tactile cells (Merkel cells)


p. 154

Figure 5-3 The Structure of the Epidermis

Thick skin LM 210

Surface

Stratumcorneum

Stratumlucidum

Stratumgranulosum

Stratumspinosum

Stratum basale

Basementmembrane

DermisPapillary layer of dermis


Figure 5-4 The Epidermal Ridges of Thick Skin

Thick skin SEM 25

Epidermalridge

Pores of sweatgland ducts


p. 154

Figure 5-5 Melanocytes

Melanocytes LM 600

Melanocytes in stratum basale

Melaninpigment

Basementmembrane


p. 156

Figure 5-5 Melanocytes

Basementmembrane

Melanosome

Keratinocyte

Melanin pigment

Melanocyte


p. 156

Figure 5-1 The Components of the Integumentary System

Cutaneous MembraneAccessory Structures

Epidermis

Dermis

Papillary layer

Reticular layer

Hypodermis

Hair shaft

Pore of sweatgland duct

Tactile corpuscle

Sebaceous gland

Arrector pili muscle

Sweat gland duct

Hair follicle

Lamellated corpuscle

Nerve fibers

Sweat gland

Artery

Vein

Fat

Cutaneousplexus


p. 151

Figure 5-10 Dermal Circulation.

Hair

Papillarylayer

Reticularlayer

Cutaneousplexus

Lymphaticvessel

Subpapillaryplexus

Capillary loop ofsubpapillary plexus

Dermalpapillae

Epidermalridges

© 2015 Pearson Education, Inc.p. 162

The Epidermal Ridges of Thick Skin

Thick skin SEM 25

Epidermalridge

Pores of sweatgland ducts


p. 154

Figure 5-9 Cleavage Lines of the Skin

ANTERIOR POSTERIOR


p. 161

Figure 5-12a Hair Follicles and Hairs.

Sebaceousgland

Arrectorpili muscle

Connectivetissue sheath

Hair

Root hairplexus

Hair follicles, showingthe associatedaccessory structures

a


p. 164

Figure 5-12b Hair Follicles and Hairs

Cross section through ahair follicle and a hair, nearthe junction between thehair root and hair shaft.

Connective tissue sheath

Hair Structure

Follicle Structure

The medulla, or

core, of the hair

contains a flexible

soft keratin.

The cortex contains thick

layers of hard keratin,

which give the hair its stiff-

ness.

The cuticle, although

thin, is very tough, and

it contains hard keratin.

The internal root sheath surroundsthe hair root and the deeper portion ofthe shaft. The cells of this sheathdisintegrate quickly, and this layer doesnot extend the entire length of the hairfollicle.

The external root sheath extendsfrom the skin surface to the hair matrix.

The glassy membrane is a thickened,clear layer wrapped in the denseconnective tissue sheath of the follicleas a whole.


Figure 5-12c Hair Follicles and Hairs.

Hair shaft

External root sheath

Connective tissuesheath of hair follicle

Internal root sheath

Glassy membrane

Cuticle of hair

Cortex of hair

Medulla of hair

Matrix

Hair papilla

Subcutaneousadipose tissue

Hair follicle

c Histological section along thelongitudinal axis of hairfollicles

LM × 60


Figure 5-12d Hair Follicles and Hairs.

Hair papilla

Connective tissuesheath of hair follicle

Glassy membrane

External root sheath

Internal root sheath

Cuticle of hair

Cortex of hair

Medulla of hair

Matrix

Hair bulb

Subcutaneousadipose tissue

d Diagrammatic view of thebase of a hair follicle© 2015 Pearson Education, Inc.

p. 164

Figure 5-13 The Structure of Sebaceous Glands and Sebaceous Follicles

Epidermis

Dermis

Subcutaneouslayer

Sebaceous follicle Sebaceous gland

Sebaceous gland LM 150

Basal cells

Mitosis and growth

Breakdown ofcell membranes

Lumen

Discharge ofsebum

Basementmembrane

Lumen(hair removed)

Wall of hair follicle


p. 166

Figure 5-14a Sweat Glands

Apocrine sweat glandssecrete a thick, odorousfluid into hair follicles.

LM 459Apocrine sweat gland

Lumen

Myoepithelial cell

Connectivetissue of dermis

Apocrinegland cells

Duct ofapocrine

sweat gland

Sectional planethrough apocrine

sweat gland

A sectionthrough a merocrinesweat gland

Sweat pore

Duct


p. 167

Figure 5-14b Sweat Glands

Duct ofapocrine

sweat gland

Sectional planethrough apocrine

sweat gland

A sectionthrough a merocrinesweat gland

Sweat pore

Duct

Merocrine sweat glandsdischarge a watery fluidonto the surface of theskin.

LM 243Merocrinesweat gland

Lumen

Myoepithelialcells

Merocrinegland cells


p. 167

Figure 5-15 The Structure of a Nail

A longitudinal section

A superficial view

A cross-sectional viewEponychium

Proximalnail fold

Lunula

Nail body

Lateral nail fold

Free edge

Directionof growth

Nailbody

Lateralnail

groove

Nailbed

Phalanx(bone of

fingertip)

Eponychium

Proximal nail fold

Nail root

Lunula Nail body

Epidermis Dermis Phalanx Hyponychium


p. 169

Figure 5-13c The Structure of a Nail

A longitudinal section

Eponychium

Proximal nail fold

Nail root

Lunula Nail body

Epidermis Dermis Phalanx Hyponychium


p. 169

Figure 5-16 Repair of Injury to the Integument (Part 1 of 4).

Epidermis

Dermis

Mast cells

Inflammatory Phase1

Bleeding occurs at the siteof injury immediately afterthe injury, and mast cells in the region trigger aninflammatory response.


p. 170


Migratingepithelialcells

Macrophagesand fibroblasts

Granulationtissue

Migratory Phase2

After several hours, ascab has formed and cellsof the stratum basale aremigrating along the edgesof the wound. Phagocyticcells are removing debris,and more of these cellsare arriving with theenhanced circulation inthe area. Clotting aroundthe edges of the affectedarea partially isolates theregion.


p. 170


Fibroblasts

Proliferation Phase3

About a week after the injury, the scab has beenundermined by epidermalcells migrating over thecollagen fiber meshworkproduced by fibroblastproliferation and activity.Phagocytic activityaround the site hasalmost ended, and thefibrin clot is dissolving.


p. 170


Scartissue

Scarring Phase

After several weeks, thescab has been shed, andthe epidermis is complete.A shallow depressionmarks the injury site, butfibroblasts in the dermiscontinue to create scartissue that will graduallyelevate the overlyingepidermis.

4

4


p. 170

A Quick Method of Estimating the Percentage of Surface Area Affected by Burns

Head 9%

Upper limb9% each

Trunk 36%(front and back)

Genitalia 1%

Lower limb18% each

Head 15%

Trunk 32%(front and back)

Lower limb17% each

Upper limb 9% each

Genitalia 1%

ADULT CHILD (5-year-old)


p. 171

© 2015 pearson education, inc. figure 5-1 the components of the integumentary system. epidermis...

Documents

pearson education

tactile cells merkel

cells diekeratinocytes

epidermisthick skinlm

thick skin onlykeratinocytes

glassy layer

basal layerattachment

various layers