- We have three kinds of tears. Basal tears are almost constant and unnoticeable; they keep our eyes moist and we produce 5 to 10 ounces a day. Reflex tears are safety responses to irritants like dust or onions. And emotional tears form when stress triggers the endocrine system to make tears. Most believe that only humans produce emotional tears.
- Basal tears are produced continuously in both humans and animals. They drain through a passageway between the eye and the nose. They keep both the eyes and the nose moist. They contain an antibacterial chemical called
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