Kevin Mackenzie, University of Aberdeen CC BY
They may look like frog eggs, but these dotted circles are slices of axons that stretch inches or even feet throughout your body. Together they form the internet of the nervous system, carrying information from place to place.
In many places, the axons bundle together into nerve tracts like this one. Here, a bulk of axons trace out the same course before splitting off to reach a specific muscle or brain area. Groupings like these start early. One intrepid pioneer axon leads the way, and others follow. The young axons stick together naturally, but when the tip finds its target, the tension of its turning can help it break away.
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