The reflex arc is the nerve pathway that is followed by reflex action. An example of the reflex arc is it happens when we accidentally touch something hot. The change in temperature is detected by the receptor first. Then electrical impulses are sent to relay neuron which is located in the spinal cord. Sensory neurons are connected to motor neurons by sensory neurons. An effector receives electrical impulses through the motor neuron. A response is produced by the effector.