Describe the route of a reflex impulse in the somatic system

Take for example - you touching something sharp and instantly moving your hand away.

Sensory neurons in your fingers detect the external stimuli of the sharp object and send a nerve impulse to the spinal cord (does not reach brain) and is sent back to a motor neurone - attached to an effector that moves the muscle and moves the hand away. This is a rapid reflex action and involuntary.