A firetruck provides water for a crew on the ground as firefighters backburned near Funny River Road Wednesday May 21, 2014 in Soldotna, Alaska. Fire crews have been battling a wildfire that has grown to more than 44,000 acres in three days.
A motor neuron (or motoneuron) is a nerve cell (neuron) whose cell body is located in the spinal cord and whose fiber (axon) projects outside the spinal cord to directly or indirectly control effector organs, mainly muscles and glands.he interface between a motor neuron and muscle fiber is a specialized synapse called the neuromuscular junction. Upon adequate stimulation, the motor neuron releases a flood of neurotransmitters that bind to postsynaptic receptors and triggers a response in the muscle fiber which leads to muscle movement.
Motor neurons' axons are efferent nerve fibers that carry signals from the spinal cord to the effectors to produce effects. Types of motor neurons are alpha motor neurons, beta motor neurons, and gamma motor neurons.There are upper motor neurons and lower motor neurons, with the cell type described above being a lower motor neuron.Upper motor neurons are cortico-spinal interneurons that arise from the motor cortex and descend to the spinal cord where they activate the lower motor neurons through synapses.pecial visceral motor neurons, also called branchial motor neurons, which directly innervate branchial muscles (that motorize the gills in fish and the face and neck in land vertebrates).