Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
|
Input/output system
|
the way the spinal cord works
Stim>receptor(sensory neuron)>spinal cord(motor neuron)>effector |
|
|
Cervical enlargement
|
nerves/neurons from the arms/shoulders (thicker)
|
|
|
Lumbar enlargement
|
Nerves/neurons from the legs(thicker
|
|
|
Conus medullaris
|
End of the spinal cord proper
|
|
|
Cauda equine
|
nerves which descend from the end of the spinal cord to exit from the same foramen used when first formed. Nerves do through saccral foramina
Safest place for a spinal tap |
|
|
Spinal cord is surrounded by...
|
bone and 3 meninges:
dura mater, arachnoid, and pia mater epidural space is in between the dura mater and bone |
|
|
Pia mater
|
"soft, gentle mother"; thin layer of CT directly on the brain
|
|
|
Arachnoid
|
Loose CT, CSF is found under this layer; whispy, spider-like
|
|
|
Dura mater
|
"tough mother"; white fibrous CT under the bone
|
|
|
Gray matter
|
neurons and cell bodies making connections. Contains cell bodies of motor neurons and interneurons. Cytoplasm is gray; not myelinated
|
|
|
White matter
|
Tracts of myelinated axons to carry impulses to and from the brain.
|
|
|
Dorsal root
|
Sensory neurons only
|
|
|
Ventral root
|
Axons of motor neurons only
|
|
|
Dorsal root ganglion
|
Sensory neuron cell bodies
most cell bodies are found in CNS those found outside are called ganglia |
|
|
Ventral root
|
motor axons only
|
|
|
Anterior/Ventral fissure
|
deep fold on ventral side
|
|
|
Posterior/Dorsal sulcus
|
fold on dorsal side
|
|
|
Gray matter of Spinal cord
|
non myelinated
|
|
|
Posterior Horn:
|
Entry point for sensory neurons
|
|
|
Anterior Horn
|
Motor neuron cell bodies
|
|
|
Lateral horn
|
Sympathetic neuron cell bodies (only found in the thoracic and upper lumbar region)
|
|
|
Gray commisure
|
connection between gray matter(usually interneurons)
|
|
|
Why are there no ventral root ganglion?
|
All cell bodies are found in the gray matter
|
|
|
White matter
|
myelinated areas bringing nervous impulses to and from the brain. The gray horns, sulcus, and fissure separate the white matter into columns or "funiculi:
|
|
|
How are funiculi named?
|
For the start and end points of their axons
Ascending =spinal cord-->brian Descending=brain-->spinal cord |
|
|
Posterior funiculi
|
Ascending tracts
carry sensory info to the brain Main tracts are ... 1) fasciculus cuneatus 2)fasciculus gracilis |
|
|
Anterior funiculi
|
Descending tracts
carry motor info from the brain *anterior spinothalamic tract-one ascending tract |
|
|
Lateral funiculi
|
mix of descending and ascending tracts
|
|
|
Why does this make sense that Anterior is descending and Posterior is ascending?
|
Sensory info comes in the back side (dorsal root)
Motor responses go out the front (ventral root) |
|
|
Reflexes
|
direct transfer of stimulus
|
|
|
How does a reflex work?
|
There is direct transfer from sensory neuron to motor neuron which allows for rapid response.
Info is sent up to the brain but the pain stimulus is immediately transferred to tje motor neuron without waiting for a response from the brain. reflexes are also important for balance. |
