A Single Axon Can Stretch Farther Than a Football Field
Some neurons in your body possess an axon that starts at the base of your spine and extends all the way to the big toe, making it longer than an American football field. This single cable sends electrical signals at speeds up to 120 meters per second, allowing you to feel and react in a fraction of a heartbeat. Despite its length, the axon is only about one-hundredth the thickness of a human hair.
💡 Fun detail:
Scientists have calculated that if every neuron in one adult brain were laid end-to-end, the total length would wrap around Earth more than four times.
Source: National Institutes of Health