Lacrimal System
There are three types of tears: basal tears, reflexive tears, and psych tears. Basal tears are produced at a rate of about 1 to 2 microliters a minute, and are made in order to keep the eye lubricated and smooth out irregularities in the cornea. Reflexive tears are tears that are made in response to irritants to the eye, such as when chopping onions or getting poked in the eye. Psych tears are produced by the lacriminal system and are the tears expelled during emotional states.
The lacrimal system is made up of a secretory system, which produces tears, and an excretory system, which drains the tears. The lacrimal gland is primarily responsible for producing emotional or reflexive tears. As tears are produced, some fluid evaporates between blinks, and some is drained through the lacrimal punctum. The tears that are drained through the punctum will eventually be drained through the nose. Any excess fluid that did not go into the punctum will fall over the eyelid, which produces tears that are cried.
Read more about this topic: Crying
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