Asked by: Joshua Smith
The nose is soft and sensitive, and the nasal passage is connected to the eyes via the tear ducts. Normally this allows the lacrimal fluid (tears) to drain through the nose. But when the fluid build-up in the nose is sufficient, the flow can block the normal draining path, so that the tears that are produced have nowhere to go.
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Authors
Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.
