Flashcards in Chapter 6:The Integumentary System Deck (100)
What does the integument system consist of?
Accessory Organs (Hair, Nails, & Cutaneous glands)
What are the 3 layers of the skin?
What type of tissue is the epidermis made of?
What type of tissue is the dermis made of?
Thick Skin (3)
-on palms and soles (corresponding areas)
-has sweat glands, but no hair follicles or sebaceous glands
-has 5 layers
Thin Skin (3)
-covers the rest of the body
-has sweat glands, sebaceous glands, & hair follicles
-has 4 layers
What are the functions of the skin? (6)
-resistance to trauma & infection
-other barriers (waterproof)
-Vitamin D synthesis
What organs help complete Vitamin D synthesis?
Skin, Liver & Kidneys
Characteristics of the epidermis? (3)
-no blood vessels
-depends on the diffusion of nutrients from underlying tissue
-contains dead cells (keratin)
What are the layers of the skin?
What cells are found in the stratum basale? (4)
Where does mitosis take place?
stratum basale & deepest cells of stratum spinosum
What happens in the stratum spinosum?
more and more keratin filaments are produced which cause the cells to flatten
Characteristics of stratum spinosum? (4)
-dendritic cells found throughout
-named after spiny appearance
-thickest layer in thin skin
-deepest cells capable of mitosis
Characteristics of stratum granulosum?
-contains coarse dark staining granules
- 3-5 layers of keratinocytes
Characteristics of stratum lucidum? (3)
-seen only in thick skin
-cells have no nucleus or organelles
-thin translucent zone (no granulation)
Characterisitcs of stratum corneum? (2)
-30 layers of dead keratinized cells
-resistant to abrasion, penetration, & water loss
5 types of cells found in the epidermis
Stem cells (2)
-undifferentiated cells that give rise to keratinocytes
-found in stratum basale
-synthesize keratin w/ greatest majority found in epidermal cells
-produced by stem cells
-occur only in stratum basale
-synthesize pigment melanin
-branched process spread among keratinocytes
tactile (merkel) cells (2)
-in basal layer of epidermis
-touch receptors associated w/dermal nerve fibers
dendritic cells (3)
-found in stratum spinosum & granulosum
-stand guard against toxins, microbes, etc
What does mitosis require?
abundant supply of oxygen & nutrients that are acquired from blood vessels
As keratinocytes are pushed up they _________
Effects on keratinocytes production (2)
-slower in old age
-faster in injury or stressed skin
What do the keratinocytes produce?
lipid filled membrane coating vesicles (lamellar granules)
What are the 3 important developments that occur in stratum granulosum?
-keratinocytes nucleus & organelles degenerate (cells die)
-granules release a protein filaggrin
-vesicles release lipid mixture that spreads & waterproofs
The water barrier is produced by which layers?
stratum granulosum & stratum spinosum