Myelinated paj fibers tshwm sim nyob rau hauv dawb teeb meem ntawm lub hlwb, qaum qaum thiab hauv nruab nrab thiab cranial paj hlwb. Unmyelinated paj fibers tshwm sim nyob rau hauv lub autonomic paj hlwb.
Puas yog tag nrho lub cev muaj zog neurons myelinated?
Piv txwv li, lub cev muaj zog neurons ntawm lub paj hlwb peripheral yog myelinatedtab sis cov neurons uas tsim lub paj hlwb tsis zoo (sympathetic thiab parasympathetic nervous system) yog unmyelinated motor neurons i.e. axons ntawm lub cev muaj zog neurons tsis muaj myelin sheath npog ncig lawv axons.
Puas yog cov neurons hauv hlwb myelinated?
Lub myelin ntawm cov neurons hauv lub hlwb yog muaj cov oligodendrocytes, thaum cov neurons nyob rau hauv lub paj hlwb peripheral yog tsim los ntawm Schwann hlwb. Lub myelin sheath tsis npog tag nrho axon; nws tawm me me ntu uncovered. Cov ntu me me no hu ua cov nodes ntawm Ranvier.
Neb twg muaj myelin sheath?
Schwann cells ua myelin hauv lub paj hlwb peripheral (PNS: paj hlwb) thiab oligodendrocytes hauv nruab nrab paj hlwb (CNS: hlwb thiab qaum qaum). Hauv PNS, ib lub xovtooj ntawm Schwann tsim tau ib leeg myelin sheath (Daim duab 1A).
Cov neurons twg tsis muaj myelin sheath?
Ib tug neuron uas tsis muaj myelin sheath ncig lub axon. Lub unmyelinated neuron cuam tshuam rau ib qho ntawm cov neurons uas tsis muaj myelin sheath (ib lub plhaub rau kev ua haujlwm sai ntawm qhov muaj peev xwm ua tau).
