INTEGUMENTARY

• What type of lever is most common in the human body?

  Class 3 Lever
• In a Class 3 Lever, where is the pull located?

  Between the fulcrum and the weight
• What are the types of ordinary body movements?

  • Abduction: away from central reference point
  • Adduction: towards central reference point
  • Flexion: decreases angle between bones
  • Extension: increases angle between bones
  • Rotation
  • Circumduction
• What is a sprain?

  Twisting, stretching, and tearing of ligaments
• What are the types of sprains?

  Grade 1, Grade 2, Grade 3
• What is a strain?

  Outstretching and tearing of muscles or tendons
• What is myalgia?

  Inflammation of muscles
• What is tendinitis?

  Inflammation of tendons between muscles and bones
• What does the integumentary system consist of?

  • Skin
  • Accessory structures: hair, glands, nails
• What is the primary function of the skin?

  Protection
• How does the skin protect against ultraviolet light?

  Reduces harmful effects of UV light
• What role does the skin play in sensation?

  Detects heat, cold, touch, pressure, and pain
• How does the skin regulate body temperature?

  Through blood flow modulation and sweat glands
• What is the normal body temperature range?

  33-37 degrees Celsius
• What happens to the skin when exposed to ultraviolet light?

  Produces a molecule transformed into vitamin D
• What is the role of 7-dehydrocholesterol in vitamin D production?

  Transforms into vitamin D when exposed to UV
• What are the types of UV radiation emitted by the sun?

  UVA and UVB
• What is the effect of UVA radiation on the skin?

  Responsible for photoaging
• What is the effect of UVB radiation on the skin?

  Responsible for sunburn
• Why is sunscreen important?

  Prevents harmful UV radiation from entering skin
• How long before sun exposure should sunscreen be applied?

  15 minutes
• What are the two types of sunscreen?

  • Mineral sunscreen: reflects sunlight, contains zinc oxide and titanium oxide
  • Chemical sunscreen: turns UV rays into non-damaging heat
• What is excretion in the context of the skin?

  Excretion of small waste products through sweat
• What are the two major tissue layers of the skin?

  • Epidermis
  • Dermis
• What type of epithelium is the epidermis composed of?

  Stratified squamous epithelium
• What is the function of melanocytes in the epidermis?

  Produces melanin
• What do Langerhans cells do?

  Part of the immune system
• What are Merkel cells associated with?

  Detecting light touch and superficial pressure
• What is the primary function of the dermis?

  Structural strength and flexibility of the skin
• What is the main type of protein fiber in the dermis?

  Collagen
• What happens to collagen production as we age?

  It decreases, forming wrinkles
• What is the subcutaneous tissue also known as?

  Hypodermis
• What is the function of keratinocytes?

  Produce keratin for durability
• What do desmosomes do in the epidermis?

  Hold keratinocytes together
• What are the five strata of the epidermis?

  1. Stratum Corneum
  2. Stratum Lucidum
  3. Stratum Granulosum
  4. Stratum Spinosum
  5. Stratum Basale
• What is the stratum corneum composed of?

  Dead squamous cells joined by desmosomes
• What is the function of the stratum lucidum?

  Provides a thin, clear zone in thick skin
• What happens to cells in the stratum granulosum?

  Nucleus and organelles degenerate and cells die
• What is the significance of the stratum spinosum?

  Produces keratin fibers and appears spiny
• What is the role of the stratum basale?

  Produces cells for the most superficial strata