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Comparison between tract and nerve

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  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...
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Difference between two tiny muscles of middle ear cavity : tensor tympani and stapedius muscles

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Difference between two tiny muscles of middle ear cavity : tensor tympani and stapedius muscles Topics Tensor tympani Stapedius Origin : Both cartilaginous and bony part of auditory tube Interior of pyramid which situated on the posterior wall of middle ear cavity Insertion Medial aspect of neck of malleus Posterior aspect of neck of stapes Blood supply Superior tympanic artery branch of middle meningeal artery Posterior auricular artery , a branch of external carotid artery Anterior tympanic artery and middle meningeal artery Nerve supply Nerve to medial pterygoid branch of mandibular division of trigeminal nerve Facial nerve Nerve related with ganglia Nerve to medial pterygoid passes through otic ganglia None Functions It tenses the tympanic membrane and push the base of stapes more tightly into the fenestra vestibule Draws the stapes later...
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Difference between malleus , incus and stapes

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1.       Difference between malleus , Incus and Stapes Topics Malleus Incus Stapes Shape like  mallet   like premolar tooth (like anvil)  it looks like stirrup Length Longest, about 8-9 mm Medium Shortest Parts Head:  Neck:  Handle: Anterior process:  Lateral process:  Body Short process :  Long process :  Head : Neck : Anterior &  posterior limbs Base or foot- plate :  Development 1 st  pharyngeal arch 1 st  pharyngeal arch 2 nd  pharyngeal arch Cartilage Develops from dorsal end of Meckel’s cartilage   Develops from dorsal extremity of Meckel’s cartilage Develops from hyoid arch cartilage Muscle attachment Tensor tympa...
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