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dontstealmypeng dontstealmypeng
wrote...
Posts: 8
Rep: 0 0
7 years ago
Which of the following is NOT a chemical barrier that helps prevent infections?
A. urine
B. mucus
C. tears
D. the pH of the blood
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Answer accepted by topic starter
bio_manbio_man
wrote...
Educator
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Posts: 33241
7 years ago
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