Answer:
Pain receptors in the skin of the foot where stimulus of pain occurs, are transmitted as action potential through sensory or motor neuron to the CNS. This impulse enters the Spinal cord through the dorsal roots, and synapse through the sensory neuron cells body with the intermediate neurons,At the same time the sensory information is transmitted to the brain.
The brain integrated this message, and impulses from the pain center of the brain is relay to the motor neuron as it synapse with the other route of the intermediate neuron.
Therefore the integrated message leaves the spinal cord through the ventral roots convey by the efferent or motor neuron. This travels down to the effectors/ muscles of the foot , which leads to raising of foots-withdrawal reflex from the nail.
The entire pathways is called reflex Arc.While the process us called reflex action.
Step-by-step explanation: