L 9 Spinal cord and spinal nerves
brain and spinal cord
Central Nervous System (CNS)
spinal cord
Extends from foramen magnum to vertebra L2 Protected by vertebrae, spinal meninges and the cerebrospinal fluid (CSF). Segmented into Cervical Thoracic Lumbar Sacral Coccygeal Gives rise to 31 pairs of spinal nerves (8C-12T-5L-5S-1C)
peripheral nerves
Spinal nerves (anterior branch) divide into various branches to form plexuses which give rise to ___________ • Cervical plexus (C1-C4) which innervates the skin and the muscles of the head, neck, superior parts of shoulders and diaphragm • Braquial plexus (C5-T1) innervates the upper limbs, some muscles in the neck and shoulders • Intercostal nerves innervate intercostal muscles and skin • Lumbosacral plexus (T12-S5) innervates the abdomen, sex organs and lower limbs
L4-L5
The lenght of the spinal cord terminates at the second lumbar vertebrae (L2) From here the spinal nerves in the lumbar, sacral and coccyx regions form roots that resembles a horse tail, the cauda equina Lumbar puncture: ＿＿＿ Cauda equina是拉丁文的horse tail 的意思，中文翻譯為馬尾，指的是脊髓(spinal cord)延伸到約L1-L2後，剩下的部分呈現散開來的構造。 馬尾症候群就是指躲在脊孔中的馬尾(cauda equina)受到壓迫，因而產生了一些神經學上的症狀。
12 cranial nerves and 31 spinal nerves
peripheral nervous system (PNS)
motor, autonomic
Gray matter (GM) contains: -Posterior horn (sensory) -Anterior horn (________) -Lateral horn (__________) 後面有感覺 前面是動作
sensory and motor, sensory and motor
White matter (WM) contains: -Posterior column (sensory) -Anterior column (_____________) -Lateral column (____________)
white matter
_____________ contains: → axons with myelin → neuroglial cells 神經膠質細胞（英語：neuroglial cell、glial cell），又稱神經膠細胞、膠質細胞，是神經系統中的組成單位之一，其角色主要為提供支持、供給營養、維持環境恆定及提供絕緣；近來亦有研究指出膠質細胞可參與訊息的傳遞。
gray matter
_____________ contains: → cell bodies of neurons → dentrites → axons without myelin → axon terminals → neuroglial cells
Spinal nerves
______________ 31 pairs of spinal nerves arise from the spinal cord through nerve roots (and rootles) and travel to specific parts of the body. -Posterior root (sensory) - Spinal ganglion (cell bodies) -Anterior root (motor) - Interneurons within gray matter -Both also carry autonomic efferencies and afferencies.
