Integumentary System

Includes all the external coverings of the body,

including the skin, nails & hair

Functions of the Skin

• Protection - covers bones & muscles; protects them from external environment

• Sensory Response - detects texture & temperature & sense pain

• Temperature Regulation - controls body temperature by lowering it through sweating or releasing thermal energy from blood vessels

• Production of Vitamin D - helps skin absorb calcium & phosphorus & promotes the growths of bones

• Elimination - eliminates water, salts & other wastes through skin pores

Epidermis

• Outermost layer of skin & makes direct contact with outside environment

• Produces melanin (pigment that protects body by absorbing some of Sun's damaging UV rays

Dermis

• Thick layer of skin that gives skin strength, nourishment & flexibility

• Contains sweat glands, blood vessels, nerves, hair follicles & muscles

Fatty Layer

• Innermost layer of skin insulates the body, acts as protective padding & stores energy

Bruises

Injury where blood vessels in

the skin are broken but

the skin is not cut or opened;

Changes color as it heals

Cuts

A break in one or more

layers of the skin

Burns

Damage to the skin caused by touching hot objects, extremely cold objects, chemicals, radiation, electricity, or friction

Healthy Skin

The Sun's ultraviolet (UV) rays can cause permanent damage to

the skin, including wrinkles, dry skin & skin cancer.

Use sunscreen, wear protective clothing & avoid outdoor activities during the middle of the day

Eat a balanced diet, apply lotion to your skin to help keep it moist & use gentle soaps to clean it

Skin & Homeostasis

• Skin & circulatory system work together & help regulate body temperature

• Skin works with nervous & muscular systems to help body react to stimuli

Integumentary System

Integumentary System

​Structures:

• Skin

• ​Hair

• ​Nail

• ​Exocrine Glands

  • ​sudoriferous glands (sweat glands)

  • ​Sebaceous Glands

  • ​Ceruminous Glands

  • ​Mammary Gland

SKIN: Epidermis

• Most superficial layer of the skin

• Protects the deeper and thicker dermis layer of the skin

• ​about 4- to 50 rows of stacked squamous epithelial cells

• ​An avascular region (does not contain blood or blood vessels

SKIN:Epidermis

​Layers

• Stratum Corneum

• ​Stratum Lucidum

• ​Stratum Granulosum

• ​Stratum Spinosum

• ​Stratum Basale

SKIN:Epidermis

​Cell Types

• Keratinocytes: (90%) of epidermal cells contains keratin, protects and waterproofs the skin

• Melanocytes: (8%) produces melanin, skin color and absorbs UV light

• ​Langerhans: (1%) Participate in immune response

• ​Merkel Cells: (.5%) sensation of touch

SKIN:Dermis

​Layers (connective tissue)

• Papillary Layer

  • ​contain nerves and blood vessels

• ​Reticular Layer

  • ​tough collagen and stretchy elastin fibers running in all direction to provide strength and elasticity

  • ​contains blood vessels

SKIN:

Below the Dermis: HYPODERMIS

• Below the Dermis:

  • ​Loose connective tissues called hypodermis subcutis

  • ​Serves as the flexible connection between the skin and the underlying (muscles, bones, fat..)