Integumentary System-Physio

Protection

Forms protective barrier against injury & UV rays.

Temperature Maintenance

Sweating, shivering, goosebumps.

Makes & Stores Nutrients (2)

• Epidermis synthesizes vitamin D3.

• Hypodermis stores adipose tissue (fat)

Sensory Reception

Detect touch, pressure, pain, temp.

Excretion & Secretion

Glands excrete salts, water & wastes.

5 Functions of Integumentary System

1. Protection

2. Temperature Maintenance

3. Makes & Stores Nutrients

4. Sensory Reception

5. Excretion & Secretion

Hair Function

BLOCKS foreign particles from entering body ex: nose hairs.

Nail Function

Protects sensitive tips of fingers & toes.

Epidermis

Surface made of dead cells.

Dermis

Contains nerve & blood vessels, sweat glands & oil glands.

Hypodermis / Subcuntaneous

Contains fat cells & blood vessels.

Epidermis photo

Dermis photo

Hypodermis / Subcutaneous

Epidermis Layers

Made up of 5 (palms/soles of feet) or 4 (rest of body divisions).

(Epidermis) Primary Tissue

Stratified squamous epithelium

(Epidermis) Basale Layer =

Deepest layer

(Epidermis Basale Layer) attached to ______& separates ____ from _____.

• basement membrane

• epidermis

• dermis

(Epidermis Basale Layer) forms _________, which are _______________ with dermis

Epidermal ridges

Increased surface area contact with dermis

(Epidermis Basale Layer) Ridges =

fingerprints

(Epidermis Basale Layer) Cell division layer ____&____

stem cells

source epithelial cell replacement

(Epidermis) Most Superficial Layer =

Stratum corneum

(Epidermis Most Superficial Layer) has _____ layers of flattened & dead epith. cells

& is most likely to be part of skin that (2)

• 15-30

• Sheds in sheets of bed.

(Epidermis Most Superficial Layer) has abundant

abundant keratin

(Epidermis Most Superficial Layer) Keratin is a ____,____________

& coats ______, forms _____, ___ & ___

• tough, water - resistant protein

• skin, hair, calluses & nails.

(Epidermis Most Superficial Layer) Keratin is a ____ layer, _______________________

• dry

• unsuitable for growth of microorganisms.

Epidermis layer is (4)

• Most superficial layer

• 15/30 layers

• dead

• oldest

Sunscreen (2)

• Extra barrier between UV rays & skin.

• Helps prevent DNA mutations in skin cells.

Melanocytes

Cells that make melanin (a pigment)

Basale layer (2)

• cell division

• youngest

Basement membrane (2)

• Epidermal ridge

• Fingerprints

Epidermis photo

Melanocytes photo

Basale layer photo

Basement membrane photo

Melanocytes found

above basement membran

Melanocytes make (3)

• Melanin (pigment)

• Provides UV protection

• Provides red/brown/tan colors to epidermis.

All individ have _____ # of melanocytes

SAME

Albinos: Melanocytes _________ produce melanin

DO NOT

Dark skin: Melanocytes produce ____ melanin

MORE

Light skin: Melanocytes produce _____ melanin

LESS

Skin Color = caused by interaction between: (2)

• Pigments found in epidermis

• Blood supply in dermis.

UV Radiation Beneficial Effects (2)

• Activates synthesis of vitamin D3 (released by liver)

• Kidney converts Vitamin into a hormone essential for calcium absorption in bone CALCITONIN.

No vitamin D =

abnormal bone growth

Harmful effects of UV radiation (3)

• Sunburn

• Wrinkles, premature aging

• Cancer

Mitosis

Cells make copies of itself

Purpose of Mitosis (3)

• Repair cells (damaged)

• Replace cells (old age)

• Growth

Cancer (3)

• Uncontrolled cell division

• Damage to DNA of cells

• Can lead to tumors

Types of Skin Cancer (3)

• Basal Cell Carcinoma

• Squamous Cell Carcinoma

• Melanoma

Basal Cell Carcinoma (2)

• Most common

• Originates in basal layer (deepest)

Squamous Cell Carcinoma

• Least common

• Originates in superficial layers of epidermal tissue

Melanoma (4)

• Most deadly

• Usually starts as atypical mole

• Cancerous melanocytes grow rapidly

• Can metastasize (spread) through immune system.

ABCD of Melanoma (4)

• Asymmetry

• Border irregularity

• Color variation or change

• Diameter

Asymmetry

If you fold it in half, two sides wouldn’t match up.

Border irregularity

Jagged or blurred edges rather than smooth, continuous line.

Color variation or change (2)

• Two or more different colors are present

• A mole has been CHANGING in any way.

Diameter (2)

• Any sudden or continuing growth.

• Any mole larger than 6mm (pencil top eraser)

Dermis location

Below epidermis

Dermis functions (5)

• Mechanical strength

• Flexibility

• Protection for underlying tissues

• Highly vascular

• Variety of sensory receptors

Dermal Tissue has (3)

• Loose (areolar) connective tissue

• Collagen fibers

• Elastin fibers

Loose (aerolar) connective tissue

Vascular (contains blood)

Collagen Fibers (2)

• Strength & durability

• With age, less collagen = thin & saggy skin.

Elastin fibers (2)

Stretch, flexibility

With age, less elastin = wrinkles

Dermal Components (2)

• Accessory organs

• Communication with other systems (Circulatory, lymphatic, nervous)

Accessory Organs

Hair & sweat glands: aid w/ temp regulation.

Circulatory (2)

• Blood vessels

• Nutrients & body temp regulation

Lymphatic

• Lymph Vessels

• Defense

Nervous (3)

• Nerves

• Sensation

• Control of blood flow & secretion

Vasoconstriction (3)

• Vessels narrow

• Aid in cold environment

• Releases LESS heat

Vasodilation (3)

• Vessels widen

• Aid in hot environment

• Releases A LOT of heat

Subcuntaneous Layer (Hypodermis) Tissue & purpose (3)

• Adipose Connective Tissue

• Provides thermal insulation

• cushions organs

Subcuntaneous Layer (Hypodermis) Facts (2)

• Stabilizes skin position

• Loosely attached to dermis (above) & muscle (below)

Deepest layer of the epidermis

&

forms new epidermal cells

Stratified basale layer

Top layer of the epidermis

&

is formed of dead kerantinized cells

Stratified corneum

Epidermis LACKS

& Hypodermis provides ____ for the body

• blood vessels

• insulation

Majority of keratin in skin is found in the ___________________________________

Epidermis, more specifically, the stratum corneum.

(hint to remember: as skin cells move up from stratum basale, they fill with keratin & die, aka keratinization)

Tattoos must be injected into the ____ layer to remain permanent.

If they were injected into the _____, then they would be too deep to see.

• Dermis

• Hypodermis