Chapter 5- Integumentary System Flashcards
What system is the first line of defense against a hostile surrounding environment?
Integumentary
What are the two components of the cutaneous membrane (skin)?
Epidermis, dermis
**Functions of skin
- Protection of underlying tissues & organs
- Excretion of salts, water, and organic wastes (glands)
- Maintenance of body temp (insulation and evaporation)
- Production of melanin
- Production of keratin
- Synthesis of Vitamin D3
- Storage of lipids
- Detection of touch, pressure, pain, temp
- Coordination of immune response
What kind of tissue makes up the epidermis?
Avascular Stratified Squamous Epithelium
Thin skin
- covers most of the body
- has 4 layers of keratinocytes
Thick skin
- covers palms of hands and soles of feet
- has 5 layers of keratinocytes
- Stratum Corneum
-Layer you see, flat dead cell, many layers thick, upper layers are continuously sluffed off
- Stratum Lucidum
ONLY FOUND IN THICK SKIN
- Stratum Granolusum
-Cells start to flatten, Plasma membrane becomes thicker, organelles and cell dies off
- Stratum Spinosum
- Spiny structure
- keratinocytes
- Stratum Basale
- Mitotically active cells
- Produce cells for all other layers
- Cuboidal shaped
- Contains melanocytes
- 1 layer of cells thick!
Keratin
Tough, fibrous protein
Decreases water loss
Makes up hair and nails
What produces orange-yellow pigment in skin?
Carotene
-carrots, sweet potatoes
What produces red-yellow/brown-black pigment in skin?
Melanin
- melanocytes
- protects skin from sun damage
Blood circulation
- Blood vessels dilate from heat, skin reddens
- Blood flow decreases, skin pales