Motor neurons transmit signals to muscles and glands throughout the body. There are two major types: the somatic motor neurons that control voluntary muscle movements and the autonomic motor neurons that control involuntary muscle movements and glands. The autonomic motor neurons are further divided into the sympathetic and parasympathetic systems.Continue Reading
The somatic motor neurons have cell bodies located in the central nervous system in either the brain, brain stem or spinal cord. They extend up all the way out to the skeletal muscles. While these are generally voluntarily controlled, reflex arcs sometimes occur, where certain stimuli cause these neurons to fire involuntarily. In this case, a sensory neuron picks up a signal, generally a pain signal, that causes the stimuli to not only travel to the brain, but also through an interneuron directly to a motor neuron. This is the cause of the involuntary movement in the knee-jerk reflex test.
The autonomic motor neurons in the sympathetic system stimulate involuntary muscles or glands to actions, while those of the parasympathetic system inhibit these actions. The cell bodies of these neurons are not in the central nervous system, but are instead in clusters of nerve cells, called ganglia, in the peripheral nervous system.Learn more about Nerves
The peripheral nervous system consists of the sensory and motor neurons. Sensory neurons are nerve cells that run from receptor cells in the body to the spinal cord; motor neurons travel from the spinal cord to the effectors.Full Answer >
A fluid flows around the vestibular system, the section of the inner ear involved with balance, impinging on specialized sensory cells and generating signals that are used by the brain to determine the body's orientation, according to Wikipedia. The vestibular system is composed of the vestibule, a network of tubes known as the semicircular canals, otoliths and a structure called the cupula, which is home to the specialized sensory cells.Full Answer >
According to the BBC, the function of nerve cells is to transmit electrical messages and signals throughout the body. There are three types of nerve cells. Sensory neurons collect and transmit information about stimuli, such as sound, light and temperature. Motor neurons transmit electrical impulses from the brain to the rest of the body and are connected to sensory neurons by specialized cells called association neurons.Full Answer >
A spinal nerve is part of the peripheral nervous system and carries motor, sensory and autonomic signals between the spinal cord and the body. Jim Swan of the University of New Mexico explains that the human spinal cord is divided into 31 segments, with nerve pairs forming at each segment.Full Answer >