Chapter 13
Spinal Meninges – Fig 13-3 are specialized membranes that cover and protect the CNS, they connect btween the craninal and the spinal menings at the skull
Dura mater
- outer covering and is very tough
Epidural space – region btw the dura mater and the walls of the vertebral canal contain loose connective tissues adipose tissuse and blood vessels
Arachnoid mater
- middle layer
Subdural space – separate the dura mater from next layer direct connect in the spinal cord
Pia mater-
inner layer that firmly down to the neural tissuse in the brain
Subarachnoid space- 
space below this layer filled with CSF Spinal tap – draw fluid out of subarachnoid layer and use for testing
Meningitis – inflammation of the meningeal membrane , bacteria or viral
Spinal Anatomy – Fig 13-2
Dorsal root
- carries sensory information back to the spine
Dorsal root ganglia- contains the cell bodies of sensory neurons
Ventral root – contains the axon of motor neuron that extend into the periphery to control somatic and visceral effectors, takes information away from spine
Spinal nerves – mixed nerves that contain sensory and motor that form at the union of dorsal and ventral roots
Enlargements – area that contain a lot of gray matter, they deal with sensory and motor of control of limbs cervical enlargement – supplies nerves to the shoulder and upper limbs lumbar enlargements- provides innervation to structures of the pelvis and lower limbs
Cauda equina – terminal part of spinal cord (looks like horses tail)
Sectional Anatomy - Fig 13-5
Anterior median fissure & Posterior median sulcus – indentation in the spinal cord that divide it into left and right halves
Gray matter
- region of integration and command initiation
Central canal – narrow canal in the middle of spinal cord surrounded by grey matter
Horns
- projections of grey matter out toward the edges of the cord
Sensory nuclei –found on the posterior horn and divided into the somatic and sensory nuclei
Motor nuclei – found on the anterior horn and divided into the somatic and sensory nuclei
Commissures – are areas where the axon cross from one side of the spinal cord to another
White matter
- carries information from place to place (myelinated portion)
Posterior white column – areas where the neurons are passing ( are based on location)
Lateral white column – areas where neurons are passing found between the posterior and anterior column
Anterior white column – areas where the neurons are passing (are based on location)
Tracts – is a bundle of axons in the CNS with uniform shape, speed and myelination
Sensory/ascending – carry sensory information towards the brain
Motor/descending – conveys motor commands to the spinal cords
Commissures – like in gray matter are locations where axons cross from one side to another
Spinal Nerves - Fig 13-6
Epineurium – outermost layer consists of a dense network of collagen fibers
Perineurium - divides the nerves into compartments that contains bundles of axon
Fascicles – bundles of axons
Endoneurium – innermost layer , surround individual axons, delicate layer
REFLEXES
Rapid, automatic response to stimuli
Response does not vary
, whenever a reflexes is activated it produces the same response
Helps preserve homeostasis
Reflex Arc - Fig 13-15
1. Arrival of stimulus and activation of receptor (stimulus)
2. Activation of an sensory neuron (receptor) (dorsal root)(Sensation relayed to the brain by axon collaterals)
3. Information processing in the CNS
4. Activation of a