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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 sympathetic and parasympathetic nervous system

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Topics Sympathetic nervous system Parasympathetic nervous system Out flow it is also known as thoraco lumbar outflow T1 to L 2 It is also known as cranio sacral outflow Following Cranial nerves are involve   3,7,9 & 10 Sacral : S2,3,4 Pre ganglionic fibres Short Longer Post ganglionic fibres Longer Shorter Ganglia Para vertebral sympathetic ganglia it is away from the target organ Small ganglia close to viscera Ex: ciliary ganglia Location of pre-ganglionic neuron •        Lateral horn cells of all thoracic segments and upper two or three lumbar segments of spinal cord •        Neurons are located in the brain stem and connected with the 3, 7, 9, 10 cranial nerves and 2,3,4 sacral segments of spinal cord Location o...
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Difference between metacarpals and metatarsals

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Difference between metacarpals and metatarsals  metacarpals metatarsals The is head is rounded The head is flattened from side to side Head is larger than the base Head is smaller than the base It  is directed below It is directed in front The shaft is of uniform thickness The shaft trappers distally The dorsal surface of the shaft has an elongated flat triangular area The dorsal surface of the shaft uniformly convex The base is irregular and projects upwards The base is set obliquely and projects backwards SN: Similarity: 1.        Both are miniature long bone 2.        Each metacarpal and metatarsal bone has  one primary ossification centre  and one secondary ossification centre. In case,  1 st metacarpal and 1 st metatarsal: one primary ossification center is situated at...
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difference between vein and venous sinus

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Difference between vein and venous sinus Vein Venous sinus From within outward it is formed by tunica intima (endothelium, subendothelial connective tissue , and internal elastic lamina ) tunica media and tunic a adventitia From within outward it is formed by endothelium,  dura mater (dense collagenous connective tissue) & periosteum Most of the veins contain valves They are valve less They contain muscular coat (tunica media ) They are devoid of muscular coat They collect deoxygenated blood from whole body They collect deoxygenated blood from the brain , meninges, diploie , internal ear and orbit They  drain blood into right atrium of heart They drain blood into internal jugular vein It contain deoxygenated blood It contain deoxygenated blood and cerebrospinal fluid Smooth muscles of blood vessel developed from...
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Difference between primary and secondary ossification

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Difference between primary and secondary ossification centre Primary ossification center Secondary ossification centre : 1.       It is the first area of a bone which starts to ossify. 1.       These are the areas of ossification that appear after the appearance of the primary ossification center. 2.       It usually appears during intra-uterine life in the central part of each developing bone 3.       Exception: carpal bones of hand 2.       Most of which appear during the postnatal and adolescent years. 3.       Exception : lower end of femur (this secondary ossification centre appear before birth) 4.       In long bones the primary ossification centers appear in the diaphysis/shaft and in irregular bones the primary cent...
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