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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 osteoblast and osteoclast

Difference between   osteoblast and osteoclast  Topics Osteoblast Osteoclast Cell morphology Cuboidal to low columnar, basophilic cytoplasm with clear area within cytoplasm due to presence of golgi complex   Large irregular shaped cell Cytoplasm acidophilic with ruffled border and underlying Howship’s lacuna Nucleus mononucleated cell , Multinucleated Size •        15-30 150–200 µm in diameter Location Bone surface: in growing bone it is situated near the periosteum in adult boen : it is situated in the endosteal surface of bone, Closing cone of resorption canals   Bone surface , cutting cone of resorption canal Percentage of all cells in the bone Ø   5% Ø   1% Life span Weeks (average 12 days) Days > 3 d...

Difference between osteocyte and osteoclast

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Difference between   osteocyte and osteoclast  Topics Osteocyte Cell morphology Small Star shape with oval cell body , cytoplasm pale with long cell processes Nucleus mononucleated cell Size 5-20 µm Location Lacunae and canaliculi of bone matrix Percentage of all cells in the bone 95% Life span Years (average 10-20 years) Precursor cells Osteoblast Differentiation process / transcription factors   Selection process from osteoblasts not known Major hormonal / regulatory receptors RANKL:, PTH Biochemical markers Dentin matrix protein 1 (DMP-1) , podoplanin (E-11 protein ) , sclerostin , fibroblastic growth factor 23 (FGF23)   Osteocyte