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How Do Our Eyes Create Tears?

Tears are secretions of the lacrimal glands or tear glands flowing from the main excretory ducts into the eyeball and eyelids. Tears lubricate the eyes and keep it clean. Tears also flow when the individual experiences extreme emotions like happiness and sadness.

There are two lacrimal glands or tear glands located above each eye behind the upper eyelids. These glands produce lacrimal fluid or tears. Tears are usually very salty. The brain commands the lacrimal glands to produce lacrimal fluid. Capillary action draws tears through the eyes surface to lubricate, wash and clean the eyes. The excess tears should collect at the lacrimal lake where tears will be channeled to the lacrimal duct which drains into the nasalacrimal duct to drain in the throat or nose. However, if the lacrimal duct is clogged or there is too much tears, the tears spill out of the eyes down the cheeks.

Tears are produced routinely in small amounts to lubricate and keep the eyes clean. This kind of tears is called the basal tears. Tears caused by strong irritating chemicals, pepper spray, tear gas, smoke or even onion vapors is known as reflex tears. It is the body’s way of washing irritants and foreign bodies. The third kind of tears is the psychic tears. This is also called crying or weeping. Strong positive or negative emotions can cause tears and crying. This kind of crying has a different chemical composition than basal and reflex tears. More protein hormones are present in this kind of tear and the hypothalamus is involved.

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