Answer: epinerium, perineurium, endoneurium
In this case, the contaminant should first
pass through the epinerium, which surrounds the total bundle of nerve fibers in
the fascicles. Then goes through the perineurium, a fibrous sheath that surrounds
and protects each fascicles and fill each spaces between these fascicles and
lastly the endoneurium, a fine connective tissue sheath that is in the inner
layer that surround and cover individual muscle fiber and finally reach the
individual axons.
