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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 gray and white rami communicans

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  Difference between gray and white rami communicans White and gray rami communicans connect the sympathetic ganglia to the spinal nerves. They are associated with the sympathetic nervous system, which is part of the autonomic nervous system responsible for the body's fight or flight response. Gray and White Rami Communicantes The gray and white rami communicantes are nerve fibers that connect the spinal nerves to the sympathetic chain ganglia in the autonomic nervous system. They play a crucial role in transmitting sympathetic nerve impulses. 1. White Rami Communicantes 🔹 Function: Carry preganglionic sympathetic fibers from   spinal nerve to   sympathetic chain ganglia . 🔹 Fiber Type: Myelinated  :so   "white" in appearance  🔹 Location: Found only at T1–L2/L3 spinal levels (thoracolumbar outflow). 🔹 Pathway: Some fibers synapse at the same level in the sympathetic ganglion. Some ascend or descend before synapsing in other...