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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 granular and agranular leukocytes

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Difference between granular and agranular leukocytes Leukocytes or white blood cells are divided into two main types according to the presence or absence of granules in their cytoplasm: 1. Granular Leukocytes These leukocytes contain visible granules in their cytoplasm and have a lobed nucleus. They include: Neutrophils (Most abundant, 50-70% of WBCs). It phagocytosis of bacteria and fungi. It has multilobed nucleus, fine granules. It is neutral (pinkish stain in H&E). Eosinophils (1-4% of WBCs)  it defend against parasitic infections, modulate allergic reactions.it has bilobed nucleus, large red/orange granules. Stain: Acidic (eosinophilic, red/orange). Basophils (Least abundant, <1% of WBCs) release histamine and mediate inflammatory and allergic responses. It has bilobed nucleus, large dark blue/purple granules. Stain: Basic (basophilic, blue/purple). 2. Agranular Leukocytes (Agranu...
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Difference between parotid and submandibular gland

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  Difference between parotid and submandibular gland Histology of Parotid Gland Type: Purely serous gland : produces watery like secretion which  rich in enzymes Histological Features: Capsule & Septa : parotid gland is surrounded by a fibrous capsule , which extends into the gland forming septa , dividing it into lobules . The Secretory Units of parotid gland is composed entirely of serous acini which is  d arkly stained, pyramidal-shaped cells with round nuclei , and basophilic cytoplasm due to rough endoplasmic reticulum (RER). It secrete amylase (digestion of carbohydrates) and antimicrobial proteins (lysozyme, lactoferrin). Duct System of parotid gland : types of ducts Intercalated ducts : it is lined by simple cuboidal epithelium. Striated ducts : it is larger, lined by simple columnar epithelium , and have basal striations due to mitochondri...
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Difference between ascending tract and descending tract

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  Difference between ascending tract and descending tract     Ascending tract Descending tract The  ascending tracts carry sensory information from the body , like pain, for example, up the spinal cord to the brain. Descending tracts carry motor information, like instructions to move the arm, from the brain down the spinal cord to the body. The ascending tracts to cerebral cortex (posterior column tracts, spinothalamic tracts) involve a chain of 3 neurons 1 st 2 nd and 3 rd order neuron   to reach the cerebral cortex The descending tract involve two sets of neuron upper motor neuron and lower motor neuron Pathway from receptors to primary sensory area 3 1 2 Pathway from primary motor area 4 to target organs (skeletal muscle , smooth muscle and gland) It carries sensory information from periphery to brain It carries motor order from brain ...
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