1. PowerPoint
Lecture
Integumentary
System
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2. Introduction
• Two or more kinds of tissues grouped together
and performing specialized functions constitutes
an organ.
• The skin and its various structures make up the
integumentary system.
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3. Skin and Its Tissues
• Composed of several tissue types
• Maintains homeostasis
• Protective covering
• Retards water loss
• Regulates body temperature
• Houses sensory receptors
• Contains immune system cells
• Synthesizes chemicals (such as vit D)
• Excretes small amounts of wastes
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4. Layers of Skin (2)
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• Epidermis Stratified
squamous
• Dermis epithelium
• Subcutaneous layer
• aka hypodermis Dense irregular
connective
• beneath dermis tissue
• some also call it
the superficial
fascia
• not part of the Adipose tissue
skin © The McGraw-Hill Companies, Inc./Al Telser, photographer
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5. Epidermis
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• Lacks blood vessels Hair shaft
• Keratinized
Sweat gland pore
Sweat
Stratum corneum
Epidermis
Stratum basale
• Thickest on palms and Capillary
Dermal papilla
Basement membrane
soles (0.8-1.4mm) Dermis
TTactile (Meissner’s) corpuscle
Sebaceous gland
Arrector pili muscle
• Melanocytes provide Sweat gland duct
Lamellated (Pacinian) corpuscle
Hair follicle
melanin Subcutaneous
layer
Sweat gland
Nerve cell process
• Rests on basement membrane
Adipose tissue
Blood vessels
Muscle layer
• Stratified squamous epithelia
(a)
Hair shaft
Epidermis
Hair follicle Dermis
Sebaceous gland
(b) 5
b: © Victor Eroschenko

6. Epidermis
There are five (5) layers of the epidermis:
• stratum corneum
• stratum lucidum
• stratum granulosum
• stratum spinosum
• stratum basale
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Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale
Basement
membrane
Dermal papilla
Dermis
(a) (b) 6
b: © The McGraw-Hill Companies, Inc./Al Telser, photographer

7. Epidermis
• Heredity and environment determine skin color
• Genetic Factors • Physiological Factors
• Varying amounts of melanin • Dilation of dermal blood vessels
• Varying size of melanin • Constriction of dermal blood
granules vessels
• Albinos lack melanin • Accumulation of carotene
• Jaundice
• Environmental Factors • Cyanosis
• Sunlight
• UV light from sunlamps
• X-rays
• Darkens melanin
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8. Dermis
• On average 1.0-2.0mm thick
• Contains dermal papillae
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• Binds epidermis to underlying Hair shaft
Sweat gland pore
Sweat
tissues Epidermis
Stratum corneum
Stratum basale
Capillary
• Irregular dense connective tissue Dermal papilla
Basement membrane
• Muscle cells – arrector pili
Tactile (Meissner’s) corpuscle
Dermis Sebaceous gland
Arrector pili muscle
Sweat gland duct
• Nerve cell processes Lamellated (Pacinian) corpuscle
Hair follicle
• Specialized sensory receptors SubcutaneousSubcutaneous Sweat gland
layer Nerve cell process
Adipose tissue
Blood vessels
• Blood vessels (a)
Muscle layer
• Hair follicles
• Glands
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9. Dermis
• There are actually two (2) layers to the dermis:
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• Papillary layer
• thin
Hair shaft
Sweat gland pore
Sweat
• superficial Epidermis
Stratum corneum
Stratum basale
• dermal papillae here Capillary
Dermal papilla
• loose areolar CT Dermis
Basement membrane
Tactile (Meissner’s) corpuscle
Sebaceous gland
Arrector pili muscle
• Reticular layer Sweat gland duct
Lamellated (Pacinian) corpuscle
• 80% of dermis
Hair follicle
SubcutaneousSubcutaneous Sweat gland
layer Nerve cell process
• dense irregular CT Adipose tissue
Blood vessels
Muscle layer
(a)
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10. Subcutaneous Layer
• Aka hypodermis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
• Loose connective Hair shaft
Sweat gland pore
Sweat
tissue and … Epidermis
Stratum corneum
Stratum basale
Capillary
Dermal papilla
• Adipose tissue Dermis
Basement membrane
Tactile (Meissner’s) corpuscle
Sebaceous gland
are present Arrector pili muscle
Sweat gland duct
Lamellated (Pacinian) corpuscle
• Insulates Subcutaneous
Hair follicle
Sweat gland
layer Nerve cell process
Adipose tissue
• Major blood Blood vessels
Muscle layer
vessels present
(a)
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11. Accessory Structures
of the Skin
• Accessory structures of the skin originate from the
epidermis and include:
• Hair follicles
• Nails
• Skin glands
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12. Hair Follicles
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• Epidermal cells
Hair shaft
• Tube-like depression Pore
• Extends into dermis
• Three (3) parts: Sebaceous
gland
• Hair root
• Hair shaft Arrector pili
muscle
Hair root
• Hair papilla (keratinized
cells)
Hair follicle
• Melanin Eccrine
sweat gland
Region of
• Arrector pili muscle cell division
Hair papilla
DermalDermal
blood
vessels
(a)
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13. Nails
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• Protective coverings Lunula Nail bed Nail plate
• Three (3) parts:
• Nail plate
• Nail bed
• Lunula
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14. Sebaceous Glands
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• Usually associated with hair Sebaceous
gland
follicles
Hair follicle
• Holocrine glands
• Secrete sebum (oil) Hair
• Absent on palms and soles
© Per H. Kjeldsen
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15. Sweat Glands
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• Aka sudoriferous glands
Hair shaft
• Widespread in skin Pore
• Originates in deeper dermis Dermal
papilla
or hypodermis
Sebaceous
gland
• Eccrine glands Duct
Hair
• Apocrine glands follicle
Eccrine
sweat
• Ceruminous glands gland
Apocrine
sweat
• Mammary glands gland
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16. Regulation of
Body Temperature
• Regulation of body temperature is vitally important
because even slight shifts can disrupt metabolic
reactions.
16

17. Regulation of Body
Temperature
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Control center
Hypothalamus
detects the deviation
from the set point and
signals effector organs.
Receptors Effectors
Thermoreceptors Dermal blood vessels
send signals to the dilate and sweat glands
control center. secrete.
Stimulus Response
Body temperature rises Body heat is
above normal. lost to surroundings,
temperature drops toward
normal.
too high
Normal body
temperature
37°C (98.6°F)
too low
Stimulus Response
Body temperature Body heat is conserved,
drops below normal. temperature rises toward normal.
Receptors Effectors Effectors
Thermoreceptors Dermal blood Dermal blood
send signals to the vessels constrict vessels constrict
control center. and sweat glands and sweat glands
remain inactive. remain inactive.
Control center
Hypothalamus
detects the deviation
from the set point and
signals effector organs. If body temperature
continues to drop,
control center signals 17
muscles to contract
involuntarily.

18. Heat Production and Loss
• Heat is a product of cellular metabolism
• The most active body cells are the heat producers
and include:
• Skeletal muscle
• Cardiac muscle
• Cells of certain glands such as the liver
• The primary means of heat loss is radiation
• Also there is conduction, convection and
evaporation
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19. Problems in Temperature
Regulation
• Hyperthermia – abnormally high body temperature
• Hypothermia – abnormally low body temperature
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20. Healing of Wounds and Burns
• Inflammation is a normal response to injury or stress.
• Blood vessels in affected tissues dilate and become
more permeable, allowing fluids to leak into the
damaged tissues.
• Inflammed skin may become:
• Reddened
• Swollen
• Warm
• Painful
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21. Healing of Cuts
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Site of injury
Blood cells
(a) (b)
Scab
Blood
clot
(c) (d) (e)
Scab
Scar
tissue
Scar
tissue
Fibroblasts
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(f) (g)

22. Types of Burns
• First degree burn – superficial, partial-thickness
• Second degree burn – deep, partial-thickness
• Third degree burn – full-thickness
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23. Rule of Nines for Adults
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Anterior head 41/2% Anterior and posterior head and neck 41/ 2% Posterior head
and neck 41/2% 9% and neck 41/2%
Anterior Anterior and Posterior
trunk posterior upper trunk
18% extremities 18%
18%
Anterior upper Anterior and Posterior upper
extremities 9% posterior trunk extremities 9%
36%
41/ 2% 41/2% 41/2% 41/ 2%
Perineum 1%
9% 9% 9% 9%
Anterior lower Anterior and Posterior lower
extremities 18% posterior lower extremities 18%
extremities
36%
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100%

24. Lifespan Changes
• Skin becomes scaly • Melanin production slows
• Age spots appear • Hair thins
• Epidermis thins • Number of hair follicles
• Dermis becomes decreases
reduced • Nail growth becomes
• Loss of fat impaired
• Wrinkling • Sensory receptors decline
• Sagging • Body temperature unable to
• Sebaceous glands be controlled
secrete less oil • Diminished ability to
activate Vitamin D
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