Final answer:
The axons of afferent and efferent neurons are organized into structures called nerves in the PNS and tracts in the CNS, with various connective tissues providing structure and nourishment.
Step-by-step explanation:
The axons of afferent and efferent neurons are typically organized into structures known as nerves in the Peripheral Nervous System (PNS) and as tracts in the Central Nervous System (CNS). Sensory axons, which are afferent, carry signals from sensory receptors towards the CNS, while motor axons, which are efferent, carry signals away from the CNS to muscles and other effectors. For example, the optic nerve is known as such in the PNS, but changes name to the optic tract once it enters the CNS, such as after the optic chiasm. Additionally, nerves contain not only axons but also various connective tissue layers, which include the epineurium, perineurium, and endoneurium, providing structure and nourishment for the nerve.