integru

• What does the word "integument" mean in Latin?


  To cover
• What components make up the integumentary system?


  Skin, nails, hair, and sweat and sebaceous glands
• What is the primary function of the skin?

  Protection
• What is the top layer of skin called?

  Epidermis
• What is the role of keratin in the epidermis?


  It makes the skin more waterproof
• What pigment is produced by cells in the epidermis?

  Melanin
• What does the dermis contain?


  Blood vessels, nerves, sense receptors, hair follicles, and smooth muscle
• What are the two types of glands found in the dermis?

  Sebaceous and sweat glands
• What is the function of the subcutaneous layer?


  It helps to insulate, store energy, and protect the body
• What are the layers of the epidermis?

  1. Stratum Germinativum (Basale)
  2. Stratum Spinosum
  3. Stratum Granulosum
  4. Stratum Lucidum
  5. Stratum Corneum
• What is the process of keratinization also known as?

  Cornification
• How long does it take for cells to move from stratum germinativum to stratum corneum?


  7 to 30 days
• What do melanocytes produce?


  Melanin
• What is the main function of keratinocytes?


  To produce keratin
• What role do dendritic cells play in the skin?


  They consume foreign substances and activate the immune system
• Where are tactile cells located?


  At the epidermal-dermal junction
• What is the dermis primarily composed of?


  Fibrous connective tissue
• What happens to the dermis when it is excessively stretched?


  It can tear, leaving stretch marks
• What are the two layers of the dermis?

  Papillary dermis and reticular dermis
• What is the primary role of the dermis?


  To sustain and support the epidermis
• What is the main component of the dermis that provides toughness?

  Collagen
• What do mast cells in the dermis contain?

  Granules of vasoactive chemicals, mainly histamine
• What are the two networks of blood vessels in the dermis?

  Superficial plexus and deep plexus
• What is the main function of the lymphatic drainage of the skin?


  To conserve plasma proteins and scavenge foreign material
• What do free sensory nerve endings in the skin detect?


  Pain, itch, and temperature
• What is the function of hair in the integumentary system?


  It consists of dead, heavily keratinized cells
• What are the two regions of hair?


  Root and shaft
• What is the function of hair follicles?


  They extend from the epidermal surface into the dermis
• What do nails correspond to in other animals?


  Hooves or claws
• What is the lunula of the nail?


  A white crescent at the base of some nails
• What are the main functions of nails?


  Protect tips of fingers and toes, provide counterpressure, and serve as tools
• What are the roles of the skin?

  1. Protection (chemical, physical, biological barriers)
  2. Temperature regulation (via vasculature & sweat glands)
  3. Vitamin D production (from cholesterol)
  4. Cutaneous sensation (temperature, touch, pressure, pain)
  5. Excretion (sweat contains nitrogen wastes)
• What is the chemical barrier provided by the skin?


  Antibacterial sebum
• How does the skin regulate temperature?

  Through its vasculature and sweat glands
• From what is Vitamin D synthesized in skin cells?


  Cholesterol
• What do sensory receptors in the skin respond to?


  Temperature, touch, pressure, and pain
• What does sweat contain that is relevant to excretion?

  Small amounts of nitrogen wastes