In PNS nerve fiber regeneration, how is a growing axon directed to its original destination?
A. Injured Schwann cells produce a trail of prostaglandins to the original destination.
B. It grows within a regeneration tube.
C. The axonal terminals grow towards the neurosoma until the two severed fragments are reunited.
D. The axon grows a collateral that is directed by growth factors secreted by the postsynaptic neuron.
Answer: B
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