A STUDY OF ANATOMY AND PHYSIOLOGY OF MOVEMENT OF LOWER set out AND THE UPPER LIMBThe procedure in lifting the leg to climb a stair is a complex one which gets a dandy amount of technology inter-transfer between the capitulum and the eventual osseous muscle . There is initiation of the movement at the brainiac which is transmitted via specialized white fibre packages to the hip flexors via the modal(a) spinal cord , involving a very complex machine at the cubicleular levelThe initiation of the process is at the check cortex (Ms I ) of the brain . The primary repel estate is located at the precentral gyrus of the frontal lobe . The area coercive the motion of the lower limbs lies towards the superior surface of the brain . deep down this area lies the cell trunk of the primary nerve cell . These nerve cells are known as upper force back neurons (UMN . These UMNs receive modulating pulse rate from the inputs from the cerebellum and the basal ganglia via the extrapyramidal pathways . These tracts modulate the staring(a) movement initiated at the frontal cortex . In hand these areas are modulated by afferent signals from ascending spino cerebellar , and spino-thalamic pathways . The complex the signal initiated at the nucleus of the cell body is transmitted electronic exclusivelyy via the axon of the myelinated neuron via the way of salutatory conduction . The myelin event which surrounds the axon of nerves that involve fast transport , breaks at intermediate component separate known as Nodes of Ranvier . The electrical impulse moves in a jumping manner at these nodes nerve contagious illness as a neural impulse generated by the system of a nerve action electric potential . Like all excitable tissue , nerves maintain a resting membrane potential that is the conflict of voltage across the membrane of the neuron . ! In neurons this value is - 70 mV . This voltage residue is maintained by the Na /K pump on the membranes .
This impulse generated at the axon hillock is transmitted via the depolarizing word form which allows sodium ions admission into cells via opening of the Na channels . This ingress of Na in one portion allows activation of other(a) Na channels , causing depolarization of the adjacent region of the neuron . Subsequently repolarization occurs via the opening of K channels , which restores the membrane potential . Thus this process continues which allows the transmission of impulse . numerous such nerves together descend as the mo ve cortico spinal tract in the pyramidal system , which travels finished the mesencephalon into the spinal cord , decussating at the level of midbrain ( 90 of the fibres decussating and forming the lateral spinothalamic tract ) and again at the level of spinal cord ( the other 10 , forming the prior(a) spinothalamic tract . It is the spring which is responsible for the lower limb movements . The cortico-spinal tract travels in the anterior horn cell of the spinal cord trough the lumbar level where they synapse with the spinal ventral root neuron (lower motor neuron . A single post-synaptic neuron receives signals from umpteen neurons . At the axon terminal , the propagation of impulses leads to release...If you want to get a full essay, order it on our website: BestEssayCheap.com
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