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Comparison between tract and nerve

  Comparison between tract and nerve Nerve Nerve contain bundle of axons (nerve fibers) in the peripheral nervous system (PNS) that transmits signals between the central nervous system (CNS) and other parts of the body. It is the most important part of peripheral nervous system Location: Peripheral nervous system. Structure: Made of axons, connective tissue layers (endoneurium: axon is surrounded by it , perineurium: bundle of axons are surrounded by it, epineurium: whole nerve trunk is surrounded by it), and blood vessels. It gets myelination by Schwann cell   Function: Carries sensory signals to the CNS (afferent) from peripheral part of body or motor signals carry from from the CNS (efferent) to target organs like skeletal muscle, cardiac muscle, smooth muscle or glands Example: Sciatic nerve, median nerve, except optic nerve (though optic nerve is technically part of CNS in develop...

Difference between lateral spinothalamic, anterior spinothalamic and tract of gracilis & cuneatus

Difference between somato-sensory pathways Topics Lateral spino-thalamic tract   Anterior spinothalamic tract Tract of gracilis & cuneatus Sensation Pain and temperature Light touch and pressure Discriminative touch, vibration , conscious muscle joint sense Receptor Free nerve ending Free nerve ending Meissners corpuscles, pacinian corpuscles, muscle spindles , tendon organ 1 st order neuron Posterior root ganglion Posterior root ganglion Posterior root ganglion 2 nd order neuron Substantia getalinosa Substantia getalinosa Nuclei gracilis and nuceatus 3 rd order neuron Ventral posterior lateral nucleus of thalamus Ventral posterior lateral nucleus of thalamus Ventral posterior lateral nucleus of...

Difference between arteriole and venule

  Difference between arteriole and venule Arteriole Venule Arterioles distribute blood to capillary beds, the sites of exchange with the body tissues.   Blood of capillaries lead back to small vessels known as venules that flow into the larger veins and eventually back to the heart. ·          The  lumina of arteriole  are much smaller than corresponding venule     ·          The  lumina of venules  are much larger   than corresponding arterioles.     ·          The  walls of the arteriole  are much thicker   than venule   ·          The  walls of the veins  are much thinner than arterioles Arteriole provides 50...