Final answer:
Collections of nerve cell bodies outside the central nervous system are called ganglia, whereas bundles of axons in the peripheral nervous system are called nerves.
Step-by-step explanation:
The collections of nerve cell bodies outside the central nervous system are called ganglia. Ganglia are localized clusters of neuron cell bodies in the peripheral nervous system (PNS). On the other hand, bundles of axons in the PNS are referred to as nerves, which are different from the central nervous system (CNS) counterpart called tracts.