Integumentary System

• Integumentary System

  • Consists of skin, hair, nails and various glands​
• Two Major Components:

  • Cutaneous membrane (skin)
  • Accessory structures ​
• Cutaneous Membrane (Skin)

  • Epidermis - superficial​
  • Dermis – underlying connective tissue​
• Accessory structures ​

  • Hair, nails, exocrine glands​
• Hypodermis (Subcutaneous Layer)

  • Loose connective tissue under the dermis​
  • Separates the integument from deeper tissues and organs​
  • Often not considered part of the integumentary system​
• Type the label

  A) Epidermis

  B) Dermis

  C) Hypodermis

  
• Five General Functions of the Integument:

  1. Protection - Skin covers underlying tissues and prevents fluid loss​
• Five General Functions of the Integument:

  2. Temperature maintenance​ - Skin regulates heat exchange with the environment​
• Five General Functions of the Integument:

  3. Synthesis and storage of nutrients​

  • Epidermis synthesizes vitamin D3 ​
  • Dermis stores lipids in adipose tissue​
• Five General Functions of the Integument:

  4. Sensory reception​

  • Receptors for pain, pressure, touch, and temperature detect stimuli and send information to nervous system​
• Five General Functions of the Integument:

  5. Excretion and secretion​

  • Glands excrete salts, water, and organic wastes​
  • Specialized mammary glands secrete milk​
• Excretion

  • is the elimination of waste material from the living organisms
• Secretion

  • is the transport of material from one part of the body to another.
• What epithelial tissue the Epidermis is?

  Stratified Squamous Epithelium
• Thick Skin

  • Five Layers (Palm and Sole)
• Thin Skin

  • Four layers (Rest of the body)
• Layers are called what?

  Strata
• Stratum Basale

  • is in the deepest layer of your epidermis.
• Strata

  • From deep to Superficial
• Three Intermediate Layers:

  • Stratum spinosum, stratum granulosum, and stratum lucidum​
• Stratum Basale

  • Also called stratum germinativum
• Stratum Corneum

  • s the outermost layer of the epidermis and marks the final stage of keratinocyte maturation and development.
• Where Stratum Basale attached?

  • Basement membrane by hemidesmosomes​
• Fingerprints

  • ridge patterns of the fingers​
• Stratum Spinosum

  • is the result of stem cell division​
• Stratum Granulosum

  • cells make a lot of keratin​
  • (Keratin) A protein that provides water resistance and the foundation for hair and nails​
• Stratum Lucidum

  • cells are densely packed into a highly keratinized layer – only thick skin​
• Stratum Corneum

  • Contains 15–30 layers of keratinized or cornified dead cells​
• Stratum Corneum

  • After two weeks in stratum corneum, shed or washed away​
• Carotene

  • is orange-yellow, accumulates in epidermis, and comes from orange-colored foods​
• Melanin

  • is brown, yellow-brown, or black, produced by melanocytes near stratum basale cells, absorbs ultraviolet (UV) radiation protecting deeper layers​
• Freckles

  • are areas of greater melanin production​
• Melanocytes

  • Produces Melanin to protect the skin from UV rays
• Albinism

  • Light colored skin or hair​
  • Melanin is not produced in melanocytes even though of normal abundance​
• Cyanosis

  • a bluish coloration, occurs when blood oxygen supplies are diminished​
• Role of Dermal Circulation

  • Oxygenated blood is bright red resulting in a flushed, red skin color when dermal blood vessels dilate​
• Vitamin D3

  • A cholesterol-related steroid in the epidermis when exposed to sunlight​
• Malignant Melanoma

  • Usually begins from a mole, and can metastasize through the lymphatic system​
• Dermal Papillary Layer

  • Named for the dermal papillae​
  • Just deep to, and projects up into, the epidermis​
  • Contains capillaries and nerves supplying the epidermis​
• Dermal Reticular Layer

  • Interwoven meshwork of dense, irregular connective tissue ​