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.
motor neuron motoneuron. postganglionic n's neurons whose cell bodies lie in the autonomic ganglia and whose purpose is to relay impulses beyond the ganglia. preganglionic n's neurons whose cell bodies lie in the central nervous system and whose efferent fibers terminate in the autonomic ganglia.reganglionic neuron. A neuron of the autonomic nervous system whose cell body lies in the central nervous system and whose axon terminates in a peripheral ganglion, synapsing with postganglionic neurons.