Why does initiation of nerve impulse occurs at the axon hillock?: (A) It is unmyelinated, (B) Due to the release of neurotransmitter, (C) It has a lower threshold than the rest of the axon, (D) None of the above
Answer is C. In motor neurons, the poion of the cell with the lowest threshold for the production of a full fledged action potential is the initial segment, the poion of the axon at and just beyond the axon hillock. Ref: Ganong's Review of Medical Physiology, 23rd Edition, Chapter 4.