This animation shows the eye' s response to invading foreign substances, resulting in blinking and the lacrimal gland' s production of tears which then pass into the nose through tear ducts.
The nervous system enables a person to blink to prevent harmful substances from getting in the eyes. During the normal course of a day, a person blinks an average of 15 times a minute to keep the eyes healthy. The lacrimal gland provides lubricating fluid for the eyes. The eyelid moves fluid from the lacrimal gland and across the eye. Blinking also provides the eyes with protection from foreign objects.
When the eye becomes irritated, the lacrimal gland produces extra tears to wash out impurities. Excess fluid drains through the tear ducts and into the nasal cavity. An abundance of tears draining through the nasal cavity may cause the nose to run and a person to sniffle.
Reviewed last on: 10/5/2008
Luc Jasmin, MD, PhD, Gene Therapeutics Research Institute, Cedars-Sinai Medical Center, Los Angeles CA. Review provided by VeriMed Healthcare Network.