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Home Q & A Board Biology-Related Homework Help Anatomy and Physiology
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Cali Fornia Cali Fornia
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7 years ago
Surface barriers, such as cutaneous and mucous membranes, serve the immune system as the:
A) first line of defense.
B) second line of defense.
C) third line of defense.
D) fourth line of defense.
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Human Anatomy & Physiology

Human Anatomy & Physiology


Edition: 1st
Author:
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macawmatanemacawmatane
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7 years ago
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Cali F. Author
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7 years ago
One more semester to go, thanks for helping me pass
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