Integumentary System Chapter 36 Section 3 Notes. Keys Lecture Outline – Integumentary System PowerPoint Notes textbook questions

Integumentary SystemIntegumentary SystemChapter 36Chapter 36

Section 3Section 3

NotesNotes

KeysKeys

Lecture Outline – Integumentary SystemPowerPoint Notes

textbook questions

FunctionsFunctions1.1. Covers and Covers and

protects the bodyprotects the body

What does the skin What does the skin protect us from?protect us from?– PathogensPathogens– InjuryInjury– Ultra-violet Ultra-violet

radiationradiation

FunctionsFunctions2. 2. Regulate body Regulate body

temperaturetemperatureHow does it How does it

regulate regulate temperature?temperature?– SweatingSweating– Dilate/constrict Dilate/constrict

of blood vesselsof blood vessels– Goose bumps Goose bumps

FunctionsFunctions

3. Excretes Waste3. Excretes Waste

WhatWhat

wastes are wastes are

excreted?excreted?

Urea Urea

as sweatas sweatsubcutaneous

FunctionsFunctions

4. Reduces water loss4. Reduces water loss

Keeps the body from drying out!Keeps the body from drying out!

FunctionsFunctions

5. Houses sensory receptors5. Houses sensory receptorsMechano Chemo

Photo

Chemo

Mechano

There are 2 main layers of skinThere are 2 main layers of skinI. Epidermis

II. Dermis

Deadkeratinocytes

Lamellar granules

Keratinocyte

Langerhans cell

Melanocyte

Merkel cell

Tactile disc

Sensory neuron

Stratumcorneum

Stratumlucidum

Stratumgranulosum

Stratumspinosum

Stratumbasale

Dermis

EpidermisEpidermis

Outer (surface) Outer (surface) layers of skinlayers of skin10-30 cells thick10-30 cells thick

Two Parts:Two Parts:

Inner part Inner part composed of composed of living cells living cells

Outer part Outer part is is of dead cellsof dead cells

Epidermis – Inner layersEpidermis – Inner layersLowest layer of cells Lowest layer of cells

reproduce and reproduce and push older cells push older cells toward the surface.toward the surface.

As cells near the As cells near the surface, they surface, they flatten and their flatten and their organelle organelle disintegratedisintegrate

Epidermis – Inner layersEpidermis – Inner layers

These cells also These cells also begin producing begin producing KeratinKeratin a tough, a tough, fibrous protein.fibrous protein.

This replaces This replaces cytoplasm. cytoplasm.

Epidermis – Outer layersEpidermis – Outer layersThe Keratin producing The Keratin producing

cells die as they cells die as they move toward the move toward the surface.surface.

Outer dead layer Outer dead layer waterproofs and waterproofs and protects inner layersprotects inner layers

It is shed continually It is shed continually and is completely and is completely replaced in 2 - 4 replaced in 2 - 4 weeksweeks

EpidermisEpidermisWhat do we find in the epidermis?What do we find in the epidermis?

MelanocytesMelanocytesWhat are melanocytes?What are melanocytes?

Cells that produce melanin.Cells that produce melanin.What is melanin?What is melanin?

A dark brown pigmentA dark brown pigmentWhat does melanin do?What does melanin do?

Gives skin it’s colorGives skin it’s colorProtects sensitive dermis from U-V radiationProtects sensitive dermis from U-V radiation

EpidermisEpidermisMelanocytesMelanocytes

Do some people havemore melanocytesthan other people?

EpidermisEpidermisSkin pigmentation is Skin pigmentation is

due to the type and due to the type and amount of melanin amount of melanin producedproduced

EumelaninEumelanin produces produces darker pigmentsdarker pigments

PhaeomelaninPhaeomelanin produces lighter produces lighter pigments and pigments and frecklesfreckles

These often occur These often occur together in varying together in varying amountsamounts

Melanocyte

DermisDermis

Deeper layers of skinDeeper layers of skin

10-20 times thicker10-20 times thicker

than epidermis.than epidermis.

Top layer arrangedTop layer arranged

In ridges.In ridges.

Why are thereWhy are there

ridges?ridges?

Dermis

DermisDermisRidges help the Ridges help the

epidermis bind to the epidermis bind to the

dermis.dermis.

The uneven ridgesThe uneven ridges

create fingerprintscreate fingerprints

Dermis

Accessory Organs of the DermisAccessory Organs of the Dermis

1. Hair follicles – tube-like depression 1. Hair follicles – tube-like depression where the hair developswhere the hair develops


2. Sebaceous glands – secret oily 2. Sebaceous glands – secret oily sebum to soften and waterproof skinsebum to soften and waterproof skin


3. Nails – protective covers of ends of 3. Nails – protective covers of ends of fingers and toes.fingers and toes.


4. Sweat glands:4. Sweat glands:– secrete wastesecrete waste– regulate heatregulate heat– produces ear waxproduces ear wax– produces milk during lactationproduces milk during lactation


5. Blood vessels – to nourish skin cells5. Blood vessels – to nourish skin cells


6. Nerves – to send and receive 6. Nerves – to send and receive messagesmessages

Subcutaneous


7. Erector pilli muscle7. Erector pilli muscle

--smooth musclesmooth muscle

-causes-causes

““goosebumps”goosebumps”

-causes-causes

hair to hair to

stand erectstand erectsubcutaneous

Subcutaneous layer – connective Subcutaneous layer – connective tissuetissue

Anchors dermis to the bodyAnchors dermis to the body

Contains fatContains fat

cells to cells to

protectprotect

and cushionand cushion

Subcutaneous layer

Self QuizSelf QuizBlood vesselsBlood vesselsConnective tissueConnective tissueDermisDermisEpidermisEpidermisFat cellsFat cellsHairHairHair follicleHair follicleMuscleMuscleNeuronNeuronSebaceous glandSebaceous glandSubcutaneous Subcutaneous

layerlayerSweat glandSweat glandSweat poreSweat pore

A.

M.

B.A.

B.

D.

H.

E.

I.

G.

C.

F.C.

D. E.

F. G.

H.

I.

J.

L.J.

K.

K.

L. M.

Disorders of the SkinDisorders of the Skin

Acne – infection of sebaceous glandAcne – infection of sebaceous gland


Benign tumor – fleshy growths on Benign tumor – fleshy growths on neck, armpits and body. neck, armpits and body.

Harmless!Harmless!

Tumor


Vascular Birthmarks – Blood vessel Vascular Birthmarks – Blood vessel abnormality affecting .5% of abnormality affecting .5% of population – darkens skinpopulation – darkens skin


Dermatitis – dry, sensitive skinDermatitis – dry, sensitive skin


Nail FungusNail Fungus


Fungal infectionsFungal infections

Athlete’s Foot

Ring Worm


Impetigo – bacterial infectionImpetigo – bacterial infection


Psoriasis – chronic inflammationPsoriasis – chronic inflammation


CancerCancerMelanomaMelanoma

CarcinomaCarcinoma


Warts- viral infectionWarts- viral infection

Plane warts

Common wart

Plantar wart

Disorders of Disorders of the Skinthe Skin

BurnsBurnsFirstFirst degreedegree

SecondSecond degreedegree

ThirdThird degreedegree

Interesting TidbitsInteresting TidbitsYour body is composed of approximately Your body is composed of approximately 100 Trillion cells100 Trillion cells

About 16% of your body weight is skinAbout 16% of your body weight is skin

The skin is completely renewed every 27 The skin is completely renewed every 27 daysdays

You will make almost 1000 new skins in a You will make almost 1000 new skins in a lifetimelifetime

If all the layers of your skin were laid out If all the layers of your skin were laid out on the ground, it would cover about 20 mon the ground, it would cover about 20 m22 or 2 parking spacesor 2 parking spaces

Interesting TidbitsInteresting TidbitsA fingernail or toenail takes about 6 A fingernail or toenail takes about 6 months to grow from base to tipmonths to grow from base to tipFingernails grow faster than toenailsFingernails grow faster than toenailsAn average human scalp has An average human scalp has 100,000 hairs100,000 hairsWe lose between 40 and 100 hairs We lose between 40 and 100 hairs per dayper dayBlondes have more hair than Blondes have more hair than brunettesbrunettes

Interesting TidbitsInteresting TidbitsFingerprints provide traction for grasping Fingerprints provide traction for grasping objectsobjectsEven identical twins have different Even identical twins have different fingerprintsfingerprintsEvery square inch of dermis contains Every square inch of dermis contains twenty feet of blood vesselstwenty feet of blood vesselsSkin on our hands and feet is thicker. Skin on our hands and feet is thicker. When we bathe, skin takes on water and When we bathe, skin takes on water and swells slightly.swells slightly.In the thicker areas, increased surface In the thicker areas, increased surface area creates crowding. The skin must area creates crowding. The skin must wrinkle to accommodate the changeswrinkle to accommodate the changes

Interesting TidbitsInteresting TidbitsFriction of the epidermis causes cell Friction of the epidermis causes cell division to increase.division to increase.This outward thickening is called a callous.This outward thickening is called a callous.Sometimes growth is inward, creating a Sometimes growth is inward, creating a corn.corn.Humans shed about 600,000 particles of Humans shed about 600,000 particles of skin per hour – about 1.5 pounds per year.skin per hour – about 1.5 pounds per year.At age 70, you will have lost about 105 lbs At age 70, you will have lost about 105 lbs of skin.of skin.

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Integumentary System Chapter 36 Section 3 Notes. Keys Lecture Outline – Integumentary System PowerPoint Notes textbook questions