The Integumentary System
Functions:
- Protection
- The integumentary system surrounds all internal organs, and protects them from the outside environment.
- Synthesis of Vitamin D
- Exposure to sunlight causes the skin to make Vitamin D, which the liver and kidney uses to create calcitriol, essential for regulating calcium and phosphorous.
- Sensory
- Nerves in the skin help us to identify touch, pain, pressure, and temperature.
- Temperature Regulation
- Sweat glands found in all regions of the skin release sweat when the body is warm. Then, once the sweat is evaporated, it causes a cooling effect on the body.
The Layers:
Epidermis
- The epidermis is the thin outer layer of the skin
- Further divided into the Stratum Germinativum below and the Stratum Corneum on top.
- Keratin, a protein produced on the outer layer, helps the skin retain moisture and keeps it waterproof.
- New skin cells are produced in the lower layer.
Dermis
- The dermis is incredibly strong, thick, and flexible.
- Made up of connective tissue called collagen and elastin.
- Inside the dermis are the sensory nerves that allow us to detect a sensation.
- The hair follicles responsible for growing hair are found in the dermis
- The sebaceous glands that produce sebum are attached to these follicles.
- The sweat glands are also found in the dermis.
Hypodermis
- Subcutaneous layer
- Storage of fatty (adipose) tissue
- Used for energy storage, insulation and cushioning
- Protection
- The integumentary system surrounds all internal organs, and protects them from the outside environment.
- Synthesis of Vitamin D
- Exposure to sunlight causes the skin to make Vitamin D, which the liver and kidney uses to create calcitriol, essential for regulating calcium and phosphorous.
- Sensory
- Nerves in the skin help us to identify touch, pain, pressure, and temperature.
- Temperature Regulation
- Sweat glands found in all regions of the skin release sweat when the body is warm. Then, once the sweat is evaporated, it causes a cooling effect on the body.
The Layers:
Epidermis
- The epidermis is the thin outer layer of the skin
- Further divided into the Stratum Germinativum below and the Stratum Corneum on top.
- Keratin, a protein produced on the outer layer, helps the skin retain moisture and keeps it waterproof.
- New skin cells are produced in the lower layer.
Dermis
- The dermis is incredibly strong, thick, and flexible.
- Made up of connective tissue called collagen and elastin.
- Inside the dermis are the sensory nerves that allow us to detect a sensation.
- The hair follicles responsible for growing hair are found in the dermis
- The sebaceous glands that produce sebum are attached to these follicles.
- The sweat glands are also found in the dermis.
Hypodermis
- Subcutaneous layer
- Storage of fatty (adipose) tissue
- Used for energy storage, insulation and cushioning
DIAGRAM
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