Answer:
(d) Electrical-->Chemical-->Electrical
Explanation:
A nerve impulse is the transmission of an electrical change along the neuron's membrane from the point at which it is stimulated (synapse). The normal direction of impulse in the body is from the cell body to the axon. This nerve impulse, or action potential, is a sudden and rapid change in the transmembrane potential difference.
Normally, the membrane of the neuron is polarized at rest, which means that the ionic constitution of the medium internal to the membrane is different from the external medium, which generates different electrical charges in one medium and the other, so this difference, ie , the potential during rest is negative (-70 mV). The action potential thus consists of a rapid reduction of membrane negativity to 0mV and inversion of this potential to about + 30mV, followed by a rapid return to values slightly more negative than the resting potential of -70mV.
Nervous impulse or action potential, therefore, is a phenomenon of an electrochemical nature and occurs due to changes in the permeability of the neuron membrane. These permeability modifications allow ions to pass across the membrane. Since ions are electrically charged particles, changes also occur in the electric field generated by these charges.
Thus, we can say that the correct answer to this question is: Electrical -> Chemistry -> Electrical
