The odd tingling sensation in bn's face and lips could indicate that the axons of his sensory neurons are impaired. if a contaminant from seafood is responsible, which is the correct order of connective tissue sheaths that the contaminant would have to pass through in order to reach individual axons?

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.  

B] nitrogen fixationmight be wrong, so correct me.want extra on your answers? just go on my account and go on questions and answer, or ask in the comments!