system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is the uvula such a sensitive gag reflex point?
gpt
The gag reflex happens due to something in the nervous system known as a reflex arc. In a reflex arc, sensory nerves transmit information to the spinal column. In the spinal column usually information travels upwards towards the brain in order to be interpreted. In a reflex arc, the interneuron in the spinal column immediately send out a signal to motor neurons to do something.

The best example is touching something hot. Once the Interneurons in the spinal column get this signal, they signal to motor neurons to move the hand away. The information is also simultaneously sent to the brain so that the brain can understand why this sudden movement just happened.

The uvula hangs down from the roof of the mouth and can work to prevent large objects from going down the esophagus. If a large object tries to go down our throat it will activate the gag reflex which should hopefully prevent choking.