Fearfully and Wonderfully Made
Your Wonderful Skin
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Skin—the largest organ of the body
Barrier against pathogens
Waterproof
The epidermis contains Langerhans cells
Secretes antibacterial substances
Tough and durable
Weighs about 8–10 pounds and area is about 22 square feet
Is rejuvenated about every 4 weeks3
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Protects against heat and cold
Stores water, fat, and vitamins, and can absorb some soluble substances
Protects underlying tissues from ultraviolet radiation
Internal mechanisms regulate cell division, DNA repair, etc., to promote healing in injured skin
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Regulation—Body temperature, synthesis in vitamin D, flow of blood, salt levels, evaporation
Contains an extensive network of nerve cells—sensors for heat, cold, touch, pain.
Has an ecosystem for all the bacteria on its surface. Microorganisms keep each other in check on healthy skin.
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But this strong protective layer can be overcome by a mosquito, and
yellow fever, zika, malaria, and other diseases result.
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