Normally, the coordinated action of the muscles of the stomach and small intestine propels the food from the stomach, through the small intestine and into the colon. This muscular action also sweeps bacteria out of the small intestine and limits the numbers of bacteria in the small intestine.
The term 'motor neuron' is usually restricted to the efferent neurons that actually innervate muscles (the lower motor neurons). A single motor neuron may innervate many muscle fibres and a muscle fibre can undergo many action potentials in the time taken for a single muscle twitch.
The definition of the lower motor neuron is the nerve cell body (soma), the peripheral axon and the nerve terminal that directly innervates the skeletal muscle. These neurons, also called Î±-motoneurons are found throughout the spinal cord in the ventral horn gray matter from C1-Cy (coccygeal) levels.