Spinal Cord Exam 3 Flashcards
The spinal cord is apart of what system
Central nervous system
The spinal cord is a link between the
Brain and the rest of the body
The spinal cord is protected by the
Vertebral canal and meninges and CSF
The CSF is housed in the
Subarachnoid space
Where does the spinal cord end?
At L1 level of the vertebral column, conus medullaris
Mostly neuronal cell bodies on inside, butterfly shaped
Gray matter
Posterior wings are
Dorsal horns
Anterior wings are
Ventral horns
White matter is mostly
Myelinated axons on outside
In unipolar neurons, the cell body has a
Single process attached
What divides the peripheral and central process
Single process
Carries sensation from skin to cell body
Peripheral process
Carries information away from cell body to spinal cord
Central process
In unipolar neurons, cell bodies are located…
Outside the spinal cord and form ganglia
In multipolar neurons, these neurons have a
Single axon and many dendritic processes
Relay impulses to muscles, glands, or other neurons
Multipolar
Functional classification of neurons
Sensory, motor, or interneurons
Also referred to as afferents
Sensory neurons
Sensory neurons characteristics
Carry sensation from skin to CNS,
unipolar neurons,
Cell bodies form ganglia
In sensory neurons, their axonal processes….
Enter the spinal cord
Motor neurons referred to as
Efferents, away from CNS
Motor neurons are…
Multipolar, deliverer impulses to muscles and glands.
In motor neurons, their cell bodies are in the…
Spinal cord and their axons project out to their targets
Also referred to as association neurons
Interneurons
Multipolar neurons and entirely located within the CNS
Interneurons
Function of interneurons
Receive info from sensory neurons and decide what to do with it.
May decide to send the info up to the cerebral cortex for awareness or to motor neurons for motor response.
Dorsal horns are comprised of cell bodies of
Interneurons, which receive input from afferents
Ventral horns are comprised of cell bodies of
Motor neurons which deliver impulses to muscles and glands
Clusters of cell bodies of unipolar neurons are…
Dorsal root ganglia
Comprised of central processes of unipolar neurons
Dorsal roots
Comprised of axons of motor neurons
Ventral roots
Spinal nerves are where
Dorsal roots and ventral roots join
Spinal nerves contain the….
Peripheral processes of unipolar neurons and axons of motor neurons
Region of the spinal cord with a pair of spinal nerves attached to it
Spinal cord segment
The spinal cord is protected by the same…
3 meninges found around the brain, and CSF
In the spinal cord, the pia matter is attached to the
Surface of spinal cord
In spinal cord, arachnoid mater is __ around the spinal cord with…
Loose, subarachnoid space containing CSF
In spinal cord, the dura mater is
The thick outer layer
Spinal nerves pass through the..
Intervertebral foramen
The spinal cord has segments defined by the…
Attachment of a pair of spinal nerves
There are how many cervical segments?
8
The thoracic region has how many pairs of spinal nerves
12
What region of spinal cord provides most of the innervation of the upper extremities
Cervical
What region of the spinal cord provides the most innervation of the lower extremities and what region contributes to the lower extremities
Most= lumbar Contributes= sacral
The lumbar region has how many pairs of spinal nerves
5
The sacral region of spinal cord has how many pairs of spinal nerves
5
One pair of spinal nerves for sensory around anus
Coccygeal region
What regions are enlarged for the extremities
Cervical and lumbar
The spinal cord ends at the
Conus medullaris, L1
The spinal cord has a collection of
Nerve roots at the end called cauda equina
Order of spinal cord regions….
Cervical Thoracic Lumbar Sacral Coccygeal
Spinal nerves leave the…
Vertebral canal by passing through intervertebral foramina
Conus medullaris
End of spinal cord
Collection of ventral and dorsal roots
Cauda equina
In a newborn, the spinal cord fills the
Vertebral canal and spinal nerves pass laterally through the intervertebral foramina
Into adulthood, the vertebral column continues to….
Lengthen after spinal cord has reached its full length
In an adult, the spinal cord fills closer to the…
End, the spinal nerves have to descend within the vertebral canal before they can pass through the intervertebral foramen
Interior end of the spinal cord
Conus medullaris
conus medullaris is located between
L1 and L2 vertebrae
Extension of pia mater off conus medullaris is called
Filum terminale
Horses tail, comprised of nerve roots from interior end of spinal cord
Cauda equina
Lumbar puncture, spinal tap, is performed below
L1 level, removes CSF from around spinal cord
