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Showing posts from October, 2024

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 Blood supply of right and left lung

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  Difference between Blood supply of right and left lung  The blood supply of  lungs involves both pulmonary circulation (for gas exchange) &   bronchial circulation (for nutrition of lung tissues). 1. Pulmonary Circulation for Gas Exchange  The right & left pulmonary arteries arise from pulmonary trunk  & supply deoxygenated blood to the lungs. Each pulmonary artery divides into lobar & segmental branches, following the bronchial tree. After gas exchange in the alveoli, oxygenated blood returns via pulmonary veins to the left atrium. 2. Bronchial Circulation for Nutritional Supply  Bronchial arteries supply oxygenated blood to lung tissues (bronchi, pleura, connective tissue). Right lung : Usually one bronchial artery , arising from the 3rd posterior intercostal artery or aorta . Left lung : Typically two bronchial arteries , arising from the descending thoracic aorta . Bronchial veins drain some blood into: Azygos vein (r...