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Dennya4 Dennya4
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6 years ago
Describe the first layer of the human protective and immune systems.
 
  What will be an ideal response?
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6 years ago
There are several layers of defense that comprise our protective and immune systems. The first layer consists of our skin and mucous membranes. Most bacteria or viruses we contact are blocked by the skin from mounting an invasion. Those that manage to penetrate the skin are vigorously attacked. Bacteria that penetrate the skin are ingested by white blood cells otherwise known as leukocytes.
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