Final answer:
The endoneurium, a form of loose connective tissue, distinctly surrounds individual axons within the peripheral nerves structures. Every single axon in grouped axons (fascicles) is encased by the endoneurium.
Step-by-step explanation:
The endoneurium cocoon in the peripheral nervous system primarily envelopes the b) axons. In the normal arrangement of peripheral nerves, axons are further gathered into groupings known as fascicles, each laden with its own connective tissue layer termed the perineurium. Nonetheless, it is the endoneurium, a substance of loose connective tissue, that individually encloses each axon. This structural framework, incorporating the endoneurium, perineurium and the outermost fibrous connective tissue layer, the epineurium, is notably aligned with the connective tissue sheaths found within muscles.
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