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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 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...
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Difference between internal and external hemorrhoids

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  Difference between internal and external hemorrhoids  Hemorrhoids are enlarged veins in the anal area that can be either internal or external. These two kinds are contrasted here: Internal hemorrhoids develop above the dentate line, which marks the start of the anal canal, inside the rectum. Unless they prolapse, they are not felt or seen during a physical examination Symptoms: Unless they prolapse, they usually don't hurt. Bleeding during bowel movements, discomfort if prolapsed, and a sense of incomplete evacuation are possible symptoms. Treatment: For severe cases, treatment options include hemorrhoidectomy or rubber band ligation, as well as lifestyle modifications and drugs to minimize swelling. External Hemorrhoids Location: External hemorrhoids develop beneath the dentate line, beneath the skin surrounding the anus. The symptoms may be unpleasant, particularly if the hemorrhoid is thrombosed (a blood clot forming inside the hemorrhoid). Swelling, itching, and p...
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Difference between male and female development of urethra

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  Difference between male and female development of urethra The development of  urethra in males & females originates from   urogenital sinus , which is derived from the hindgut endoderm during embryonic development. The process differs significantly between male and female sexes due to the influence of sex hormones. 1. Development of Male Urethra Origin: The male urethra develops from   urogenital sinus and extends into the phallus . Stages of Development: Prostatic and membranous urethra : Derived from the pelvic part of the urogenital sinus. Penile (spongy) urethra : Derived from the phallic part of the urogenital sinus. Glans urethra : Formed by canalization of the ectodermal cord from the tip of the glans penis. Hormonal Influence: Testosterone, via dihydrotestosterone (DHT) , plays a crucial role in urethral elongation and closure. Clinical Correlation: Hypospadias : Incomplete fusion of urethral folds results in an abnormally placed ureth...
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Difference between lesion of oculomotor, trochlear and abducent nerve

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  Lesion of nerves supply extraocular muscle Nerve Lesion Oculomotor nerve lesion down and abducted eye Trochlear nerve lesion Upward and adducted eye Abducent nerve lesion Adducted eye ' The trochlear nerve innervation, functions of muscles and lesion   Innervation Function Lesion Extraocular muscle Superior oblique   Intorsion (medial rotation), depression and abduction, respectively. Trochlear nerve palsy results in upward deviation of the eye (hypertropia). The abducent   nerve innervation, functions of muscles and lesion   Innervation Function Lesion Extraocular muscle Lateral rectus   Abducts the eyeball. Trochlear nerve palsy results in upward deviation of the eye (hypertropia). Lesion of oculomotor nerve The oculomotor nerve innervation, functions of muscles and lesion : L...
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Difference between gray and white rami communicans

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  Difference between gray and white rami communicans White and gray rami communicans connect the sympathetic ganglia to the spinal nerves. They are associated with the sympathetic nervous system, which is part of the autonomic nervous system responsible for the body's fight or flight response. Gray and White Rami Communicantes The gray and white rami communicantes are nerve fibers that connect the spinal nerves to the sympathetic chain ganglia in the autonomic nervous system. They play a crucial role in transmitting sympathetic nerve impulses. 1. White Rami Communicantes 🔹 Function: Carry preganglionic sympathetic fibers from   spinal nerve to   sympathetic chain ganglia . 🔹 Fiber Type: Myelinated  :so   "white" in appearance  🔹 Location: Found only at T1–L2/L3 spinal levels (thoracolumbar outflow). 🔹 Pathway: Some fibers synapse at the same level in the sympathetic ganglion. Some ascend or descend before synapsing in other...
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Difference between location, functions & development of different skin cells

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  Difference between location, functions & development of different skin cells Cells of skin Location Functions Development Keratinocytes stratum basale  It forms barrier against environmental damage by heat, UV radiation, dehydration, pathogenic bacteria, fungi, parasites, and viruses. Surface ectoderm Melanocytes Stratum basale Melanocytes are well known for their role in skin pigmentation, and their ability to produce and distribute melanin has been studied extensively Neural crest Langerhans cells Stratum spinosum These cells act as the outermost guard of the cutaneous immune system and are likely to induce the first reactions against pathogens encountered via the skin Fetal Langerhans cells from Primitive yolk sac in fetal life , in adult Langerhans cells   from feta...
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