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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 rough endoplasmic reticulum and smooth endoplasmic reticulum

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difference between rough endoplasmic reticulum and smooth endoplasmic reticulum
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Difference between somitomere and somite of paraxial mesoderm

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  Difference between somitomere and somite Somitomeres and Somites: Key Differences and Development Both somitomeres and somites originate from the paraxial mesoderm and play crucial roles in the formation of the axial skeleton, muscles, and dermis.  1. Somitomeres 🔹 Definition: Somitomeres are loose masses of mesoderm that appear in a cranial-to-caudal sequence along the embryonic axis before forming somites. 🔹 Characteristics: First seen in the paraxial mesoderm during the third week of development. Less organized than somites. Found in the head and neck region (first 7 pairs do not form somites). Contribute to craniofacial muscles, pharyngeal arches, and extraocular muscles . 🔹 Fate: The first 7 pairs contribute to head and neck structures . Caudal somitomeres condense into somites in the occipital and trunk regions. 2. Somites 🔹 Definition: Somites are well-organized, paired blocks of mesoderm that develop from somitomeres in the occipital to sacral regio...
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Difference between general sensation and special sensation

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  Difference between general sensation and special sensation General and Special Sensations in the Nervous System The nervous system processes different types of sensations through the somatic and special sensory pathways . These sensations help us interact with our environment and maintain body functions. 1. General Sensation 🔹 Definition: General sensation refers to the sensations perceived from the skin, muscles, joints, and internal organs . 🔹 Pathway: Carried by the somatic sensory system via the spinal cord and brainstem . 🔹 Types: Exteroception (External Sensation) → From the skin Touch (Fine & Crude) Pressure Temperature (Hot & Cold) Pain (Nociception) Proprioception (Position Sense) → From muscles, tendons, and joints Joint Position Sense Vibration Sense Kinesthesia (Movement Awareness) Visceral Sensation → From internal organs Distension of organs (e.g., stomach, bladder) Pain from ischemia or inflammation 2. Special Sensation 🔹 Definition: Special se...
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