Axon Arbor of a Neuron (image) University of California - San Diego Share Print E-Mail Caption Stylized axon arbor of a neuron. Yellow circle: root vertex at the axon initial segment; red circles: bifurcation vertices; black circles: terminal vertices at the axon's synaptic terminals. Credit Image courtesy of Francesca Puppo. Usage Restrictions With credit Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.