Peripheral Nervous System and Spinal Cord Flashcards
What type of encapsulated receptor senses muscle length?
muscle spindle
What type of encapsulated receptor senses muscle tension?
golgi tendon organ
If a muscle is stretched, what encapsulated receptor(s) will be activated?
muscle spindle
If a muscle contracts to lift the forearm, what type of encapsulated receptor(s) will be activated?
both muscle spindle fibers and golgi tendon organs
If a muscle contracts isometrically, what type of encapsulated receptor(s) will be activated?
only golgi tendon organ
T/F: Each dorsal root has a dorsal root ganglion and contains cells bodies of sensory neurons.
True
Where are the two spinal cord enlargements located?
Cervical enlargement: C5-T1
Lumbar enlargement: L2-S3
Where do dorsal rootlets enter the spinal cord?
posterolateral sulcus
Where do ventral rootlets leave the spinal cord?
anterolateral sulcus
What region of the spinal cord does this section come from?
lumbosacral
What region of the spinal cord does this section come from?
thoracic
What does the posterior intermediate sulcus separate?
posterior funiculi
What do the two red asterisks indicate in this picture? What is the function of this area of the spinal cord?
substantia gelatinosa; pain and temperature
Lamina #2 is also known by what name?
substantia gelatinosa
Here’s an easy one:
Where is the white matter located in the spinal cord?
White matter is found on the oustide. Grey matter is found on the inside
In this image, what does the most medial arrow indicate? What do the two lateral arrows indicate?
All of the arrows point to alpha motor neurons.
The medial clusters control axial muscles
The lateral clusters control limb muscles
What do lower motor neurons (or alpha neurons) control?
Where are they located?
Skeletal muscle
anterior horn of the spinal cord
What do gamma-motor neurons innervate?
muscle spindles
In what section of the spinal cord would you find preganglionic sympathetic neurons?
intermedolateral cell column, lateral extension of gray matter
T1-L3
What is clark’s nucleus and where is it found?
What does it do?
collection of neurons on medial surface of intermediate gray matter from T1-L2
It acts as the relay nucleus for transmission of info to cerebellum, proprioceptive info from leg
It is indicated by the “C” in the image
Identify all of the structures indicated
A: corticospinal tract
B: substantia gelatinosa
C: fasciulus cuneatus
D: fasciculus gracilis
E: dorsal gray horn
F: ventral gray horn
G: lateral gray horn
H: spinoreticular & spinothalamic tracts
At what level does the spinal cord end?
L1/2
Where is a lumbar puncture performed?
L4-5
