Nerves Coursework Example | Topics and Well Written Essays - 1000 words

Nerves - Coursework Example Motor neuron functions by taking response or information from the brain to the organs or muscles which are referred to as the effectors (Starr et al, 2012 p.555). The information is taken by the motor neuron through the dendrites which then relays the same information to the cell body through the synaptic endings. Within the cell body of a motor neuron, there is axon which then transmits the information to the axon terminals which finally connect with the muscles (Chiras, 2014 p.228). These are referred to as the motor end plates and play an important role in relaying the information to the muscles for the necessary action. All neurons within and outside the central nervous system contain cytoplasmic extensions known as axons upon which impulses are conducted. The axons are often very long but thin, for instance axons connecting the foot and spinal cord can be up to one meter (Palastanga, 2006 p.15). The dendrites are branched fibres upon which nerve impulses are generated and transmitted through the axon which brunch into many times as it approaches its end. Myelin sheath is a glistening fatty sheath that covers the axon and is normally the expanded plasma membrane of an accessory cell known as Schwann cell. The node of ranvier is the point at which the sheath of one Schwann cell meets the other and it plays an important role in the propagation of nerve impulses (Brown, 2001 p.2). A reflex action is a spontaneous, fast and predictable motor response to stimulus which is repeated in the same manner whenever the same stimulus is presented (Clark, 2005 p.217). A reflex arc is completed by five components including the stimulus receptor, which is a group of nerve endings or a specialised cell which respond to the cell stimuli and receive the stimulus from internal or external environment. The second is the sensory neuron known as afferent neuron and is found in peripheral ganglion like dorsal root ganglion. Sensory neurones transmit impulses