Integumentary System Topics To Study – ANSWER KEY

  • ABCD Rule and how to identify melanoma

  • Importance of Using Sunscreen

Sunscreen

Since the number one risk factor for skin cancer is sun exposure, the use of sunscreen is the best

Prevention.

UV-A radiation will not cause sunburns, but can still

increase the risk of skin cancer. Only broad-spectrum sunscreens actually block both UV-A and

UV-B radiation.

  • Diagram (epidermis, dermis, hypodermis, hair follicle, arrectorpili, sudoriferous gland, sebaceous gland)

  • Layers and characteristics of the epidermis

Epidermis—outer layer

Stratified squamous epithelium

Can become keratinized (hardened by keratin) to prevent water loss

Avascular (no blood supply of its own)

Most cells are keratinocytes (cells that produce keratin – a fibrous protein that makes the epidermis tough)

Dermis

Dense connective tissue

Subcutaneous tissue (hypodermis) is deep to dermis

Not technically part of the skin

Anchors skin to underlying organs

Composed mostly of adipose tissue

Layers of the Epidermis and what are they:

Summary of layers from deepest to most superficial

Stratum basale

Stratum spinosum

Stratum granulosum

Stratum lucidum (thick, hairless skin only)

Stratum corneum

  • Melanin/melanocytes

Pigment (melanin) produced by melanocytes

Melanocytes are mostly in the stratum basale

Color is yellow to brown to black

Amount of melanin produced depends upon genetics and exposure to sunlight

  • Functions of skin
  • Protects deeper tissues from:
  • Mechanical damage (bumps)
  • Chemical damage (acids and bases)
  • Bacterial damage
  • Ultraviolet radiation (sunlight)
  • Thermal damage (heat or cold)
  • Desiccation (drying out)
  • Aids in body heat loss or heat retention as controlled by the nervous system
  • Aids in excretion of urea and uric acid
  • Synthesizes vitamin D
  • Layers of hair
  • Hair anatomy
  • Central medulla
  • Cortex surrounds medulla
  • Cuticle on outside of cortex
  • Most heavily keratinized
  • Nails
  • Free edge
  • Body: visible attached
    portion
  • Root: embedded in
    skin
  • Cuticle: proximal nail
    fold that projects onto
    the nail body
  • Causes of abnormal skin color

Redness (erythema)—due to embarrassment, inflammation, hypertension, fever, allergy, or conditions like rosacea

Pallor (blanching)—due to emotional stress such as fear, anemia, low blood pressure, impaired blood flow to an area

Jaundice (yellowing)—liver disorder

Bruises—hematomas

  • Burns (classify and explain)
  • First-degree burns
  • Only epidermis is damaged
  • Skin is red and swollen
  • Second-degree burns
  • Epidermis and upper dermis
    are damaged
  • Skin is red with blisters
  • Third-degree burns
  • Destroys entire skin layer;
    burned area is painless
  • Burn is gray-white or black