Why do we cry?

Nothing but a tear in your eyes ...

Tears are made by glands that are above the eyelid. They are called the lacrimal glands. These glands produce tears to cleanse or protect the eyes. Our glands make it all the time. But when you are sad, they produce much more. Once the brain decides, tears flow into channels, which serve to evacuate them. And sometimes it overflows.

If our nose is runny when we cry, it is because the excess tears run down a canal that connects the eyes to the nostrils. It is called the nasolacrimal duct.