Clin Phys 7 Flashcards
(194 cards)
What is the function of the skin?
- protective barrier
- key for regulating body temperature
- provides sensory information
- limited importance in waste removal & vitamin synthesis (vitamin D)
What is the skin an important barrier for?
- mechanical, chemical or thermal injuries
- barrier to infection
- reduces heat, fluid, electrolyte loss
T/F: The skin is the largest & heaviest organ
True
How much does skin weigh?
8 lbs
What are the layers of the skin?
- epidermis
- dermis
- subcutaneous/hypodermis
Where is skin thick? Thin?
thick: palms and soles (epidermis 0.4-1.4 mm)
thin: everywhere else (epidermis: 0.075-0.15)
What is the epidermal layers outermost to innermost?
- stratum corneum
- stratum lucidum (only in thick)
- stratum granulosum
- stratum spinosum
- stratum basale
What epidermal layer only present in thick skin?
stratum lucidum
What is the location of the corneum?
most superficial layer
What is the layer size of the corneum?
15-30 cells
What is the function of the corneum?
- most important component of the barrier
- prevents penetration microbes
- prevents dehydration
- mechanical protection
T/F: Skill cells in corneum are dead
True
What is corneum full of?
keratin and flaggrin
What is keratin and flaggrin held together by in the corneum?
tight junctions, desmosomes
What does flaggrin help keratin do?
aggregate into large macrofibrils
Where is lucidum located?
immediatley below corneum
What is the layer size of lucidum?
3-5 cells
T/F: cells in lucidum are dead
true
What is the function of lucidum?
similar to corneum
Where is granulosum located?
between the corneum and spinosum
What is the layer size of granulosum?
3-5, flattened and compacted
What are the functions of granulosum?
- Living cells that are re-organizing keratin and associating it with filaggrin and other proteins
- Lamellar granules – lipid-rich, layered granules that help reduce water loss
Where is spinosum located?
superficial to basal
What is the layer size of spinosum?
8-10 cell layers