Structures that produce, distribute, and carry away tears. An almond-shaped gland above the outer corner of each eye secretes tears between the upper eyelid and the eyeball. Tears moisten and lubricate the conjunctiva (the membrane that lines the eyelid and covers the white of the eye) and then flow into the barely visible openings (near the inner corners of the eyelids) of the tear ducts, which lead to the nasal cavity. Oil (from sebaceous glands on the edge of the eyelid) keeps tears from spilling out unless secretion increases because of crying or a reflex triggered by stimuli such as eye irritation, bright lights, or spicy foods.
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A duct may refer to:
Duct cleaning: the ICS interview.(specialists Gary Kruse and Richard Wade discuss the work)(Interview)(Industry Overview)
May 01, 2003; In order to do the best job possible of providing an introductory overview of duct cleaning, ICS went to two of the...