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(Neuron) (Spinal Cord and Brain) Neuroglia (Support) Neuroglia 210 اوم څپرکې عصبي نسج (NERVOUS TISSUE) (impulse) (neuron) (spinal cord and brain) neuroglia (support) neuroglia ٧- ١ شکل دماغ 1012 211 اوم څپرکې عصبي نسج (axons) (NEURON STRUCTURE) cell body Cell body perikaryon Soma ٧-٢ شکل دنيوران جوړښت centrioles granules basal body nissl substance 212 اوم څپرکې عصبي نسج Endoplasmic Reticulum neurotransmitters neurofibrils microtubules microfilaments neurofibrils microtubules substantia (pigmented granules) nerumelanin nigra lipofuscin cell body neuritis Dendrites Axons cell body Dendrites nissle dendrites dendrites granules dendrites cell body 213 اوم څپرکې عصبي نسج axon nissle granuls (axon and dendrites) axon cell body dendrites cell body MAP-2 dendrites dendrites nissl granules axon cell body cell body initial segments axon hillock hillock Schwann cells (sheath) oligodendrocytes Schwann cells Schwann cell ٧- ٤ شکل Schwann cells mesaxon 214 اوم څپرکې عصبي نسج (mesaxon) mesaxon myelin sheath schwann cells myelin sheath neurolimmal sheath neurilemma Schwann cell sheath myelinated axons (myelin sheath) axons Schwann cells myelin sheath myelin 215 اوم څپرکې عصبي نسج node of Ranvier myelin sheath (nodes of Ranvier) (Internode) unmyelinated axons myelin sheath mesaxon Schwann cells Schwann cell body collaterals telodendria boutons terminal boutons of terminaux synapse ganglions synapse 216 اوم څپرکې عصبي نسج dendrites 6,8,3 (nerve fibers) cell body cell bodies cell bodies 120µm cell body 5µm ٧-٨ شکل داکسون او cell body نيوران ارتبات multipolar neurons (bipolar neuron) unipolar neuron bipolar neuron (pseudounipolar neuron) ٧-٩ شکل دنيوران مختليف ډولونه 217 اوم څپرکې عصبي نسج cell bodies cell bodies cell body stellate neuron pyramidal neuron nissle Nissl substances substances golgi Type-I golgi type-II cell body microneurons (myelin sheath) (myelinated and unmylinate neurons) dendrites dendritic field dendrites dendritic fields dendrites synapses 218 اوم څپرکې عصبي نسج axon hillock action action potential potentials unmyelinated (voltage sensitive channels) (axoplasmic flow) (axoplasmic flow) (0.1-2mm ) (slow transport) rapid transport (100-400mm/day) vesicles polio virus DENDRITES a MAP-2 microtubules dendrites dendrites b spine apparatus actin filaments dendrites c dendrites d 219 اوم څپرکې عصبي نسج stellate cells dendritic fields pyramidal neuron dendritic field cerebellum golgi dendritic fields dendritic tree 80% neuron synapses dendrite dendrites Dendrites 1,5,3 (SYNAPSE) synapse synapse axodendritic synapse synapse dendrites synapse cell body axosomatic synapse Axoaxonal synapse synapse initial segments thalamus dendrites presynaptic dendro-dedritic dendro-axoonic synapses synapse cell body cell body (somato-somatic synapse) synaptic Bag bouton (Single bulb-like end) 220 اوم څپرکې عصبي نسج synapse dendrites dendrite (serial synapse) bouton (complex synapse neuroglial cells synapse) cerebellum synaptic glomeruli lateral geniculate body olfactory bulb (synapses) synaptic cartridge o synapse presynaptic postsynaptic presynaptic bouton axo-dendritic synapse o dendrite synaptic bag postsynaptic process synaptic cleft (cleft) o cleft (granular) presynaptic postsynaptic synaptic webs 221 اوم څپرکې عصبي نسج presynaptic postsynaptic o (active zone) synapse (neurotransmission) synaptic vesicles presynaptic bouton o tubules microtubules synaptic vesicles Postsynaptic o postsynaptic presynaptic endoplasmic reticulum spectrin F-actin NEUROTRANSMITTERS synapse synaptic vesicles neurotransmitters neurotransmitters (nerve terminals) (impels) synaptic cleft depolarize postsynaptic neurotransmitters postsynaptic presynaptic neurotransmitters postsynaptic hyperpolarization membrane 222 اوم څپرکې عصبي نسج synaptic cleft action potential voltage neurotransmitters synaptic cleft neurotransmitters postsynaptic membrane depolarization postsynaptic membrane neurotransmitters synapse hyperpolarization noradrenaline acetylcholine neurotransmitters adrenaline cholinergic adrenergic neurotransmitters neurotransmitters histamine dopamine neurotransmitters serotonin synapses glycine aspartate glutamate Gama-amino butyric acid(GABA) neurotransmitters synopses neurotransmitter synapse synapse dendrite synapses neuromediators neurohormons neuromediation synapse 223 اوم څپرکې عصبي نسج CSF(cerebro spinal fluid) synaptic synapse neuromodulators neurotransmitters neurotransmitters peptides cholecystokinin somatostatin vasoactive intestinal polypeptides(VIP) substance P 3,1,9 (CCK) synapse synapse neurotransmitters neurotransmitters Acetyl choline Glutamine Serotonin Noradrenaline Adrenalin Dopamine GABA glycine Synapses (neurotransmitters) synapse synapses postsynaptic presynaptic ultrastructure 224 اوم څپرکې عصبي نسج type-1 synapses 1 synaptic cleft presynaptic 30nm type- II synapses 2 20nm synaptic cleft synapses (neurotransmitters) retina synaptic ribbon spine apparatus (electrical synapses) neurotransmitters neurotransmitters 4nm connexins nexin gap junction (spinal cord and Brain) 225 اوم څپرکې عصبي نسج hippocampus Grey and white matter (white matter) (Grey matter) cell bodies grey matter unmylenatid fibres dendrites myelinated fibres white matter (white and grey matter) myelin grey matter white matter brain spinal cord neuroglia brain stem(medulla oblongata, pons and med brain) grey matter spinal cord cerebrum cerebellum grey matter grey matter white matter (cortex) 226 اوم څپرکې عصبي نسج nuclei (grey matter) nuclei cell bodies grey matter nuclei cell bodies ganglion nuclei cell bodies ganglion nerve plexuses cell bodies ganglionated plexuses grey matter (bundle) nuclei nerve tract 227 اوم څپرکې عصبي نسج lemnisci fasciculi funciculi (cerebellar and cerebral hemispheres) brain stem peduncle (nerve peripheral nerves fibres) neuropil 5,10,3 neuropil neuroglial peripheral nerves nerve fibres spinal cord a motor fibres efferent fibres grey matter brain stem spinal cord cell bodies afferent b fibrs sensory fibers 228 اوم څپرکې عصبي نسج ganglion cell bodies Afferent ganglia spinal cord (dorsal nerve root) unipolar unipolar ganglions afferent nerve fibre afferent fibres dendrites axis cylinder myelin sheath axis cylinder axolemma nodes node of Ranvier internode myelin sheath Schwann cell segment neurilemma endoneurium (CT) endothelial cells fibroblasts Fasciculi macrophages perineurium 229 اوم څپرکې عصبي نسج epineurium unmyelinated fibers myelinated fibers Type –A 30-120m/sec 1-2µm myelinated Type-A Gamma( Aᵞ) delta(Aδ) alpha(Aα) Type-A Motor type- A fibers Aα Aᵞ Aδ Sensory type A fibers encapsulated receptors Aα (primary sensory afferent) (secondary efferent) 230 اوم څپرکې عصبي نسج Nociceptors thermo receptors Aδ په محيطي عصبي سيستم کې دعصبي تارونوطبقه بندي .)٧- ٢ چارټ( Afferent)دCNS په Efferent)دمحيط په فرعي ډولونه ډولونه لور( لور( دپوست له A Alpha (α) To extrafusal muscle fibers encapsulated R ،بندونواوعضﻻتو له دواړه ډولونوته (Delta(δ thermoreceptors او nociceptors. Group I,II) Gamma(ᵞ) To intrafusal muscle fibers له جلد،غړو B Preganglionic اودعضﻻتودمنضم نسج autonomic له free nerve ending څخه (group III) C Postganglionic Interoceptive fibers او autonomic thermoreceptors او nociceptor څخه (Group iv) Type-B 3µm 4-30m/sec myelinated fibers preganglionic autonomic efferent fibers (group III) Type- C unmyelinated type-B type –A 0.5-4µm 0.5-4m/sec postganglionic autonomic 231 اوم څپرکې عصبي نسج (pain) (nociceptors fibers from connective tissue of muscles) (group-iv) thermo receptors (cutaneous nerve) dorsal root unmyelinated ventral N roote myelinated unmyelinated autonomic nerve fibers preganglionic nerve myelin sheath major dense line period line minor dense line intra-period line (incisures of Schmidt lanterman) 232 اوم څپرکې عصبي نسج Schmidt laterman cleft i period line perineural ii perioxonal space space intraperiod line Nodes of Ranvier myelin (internode) node of Ranvier N of R internode 233 اوم څپرکې عصبي نسج 150- 1500µm node Node of Ranvier node (jump) saltatory conduction node unmyelinated neurons saltatory axolemma (node of Ranvier) paranodal bulb myeline sheath node bulb node gap substance node of Ranvier paranodal (axolemma) myelin glycosphingolipid phospholipid cholesterols 234 اوم څپرکې عصبي نسج 1µm 1.5µm (unmyelinated) (long internode) nodes internode oligodendrocytes myelination PNS- node glial cells CNS compound node CNS=central PNS=peripheral nerve system nerve system Blood nerve barrier blood nerve barrier (capillaries) tight junction endothelium 235 اوم څپرکې عصبي نسج perineurium Schwann cells 10,6,9,3 (DEGENERATION AND REGENERATION OF NEURON) (distal) (proximal) cell body (granules) neurofibrils (staining) macrophage 236 اوم څپرکې عصبي نسج Proximal cell body retrograde degeneration cell body chromatolysis (cell body) cell body nissl substance cell body chromatolysis cell body reverse 237 اوم څپرکې عصبي نسج synapse trans neuronal degeneration cell body cell body nodes distal F synapse G,H I J (regeneration) scar tissues 238 اوم څپرکې عصبي نسج (Peripheral nerve ending) efferent afferent afferent efferent neuromuscular junction 3,1,5 neuromuscular junction Sensory Receptors (receptors) (cutaneous receptors) a exteroceptors exteroceptive receptors proprio-ceptors proprioceptive receptors b 239 اوم څپرکې عصبي نسج interocetors interoceptive receptors c carotid carotid body sinus d nociceptors (special sense receptors) e (taste) (smelling) (hearing) (vision) exteroceptors Mechanoceptors a fast adapting slow adapting chemoreceptors b buds carotid body retina cones rods photoreceptors c thermoreceptors d osmotic pressure osmoreceptors e 240 اوم څپرکې عصبي نسج polymodal receptors somata spinal ganglia neuronal
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