PNS Anatomy Flashcards
Are cranial nerves in the CNS or PNS?
PNS
Are unipolar or multipolar neurones most commonly associated with movement?
Multipolar
What part of the spinal cord marks the division between upper and lower motor neurones?
Anterior horn of the spinal cord
Are spinal nerves of all the same modality or mixed nerves?
Mixed
Do spinal nerves supply the viscera or the soma?
Soma
Where exactly do spinal nerves lie?
Within the intervertebral foramina
What do spinal nerves connect with once they leave the intervertebral foramina?
Rami (and then the structures of the soma)
What connects the spinal nerves to the spinal cord segment of the same number?
Roots and rootlets
Which type of axons (sensory or motor) pass from the spinal nerve into the posterior root then into posterior rootlets and then into the posterior horn of the spinal cord?
Sensory
What type of axons (sensory or motor) pass from the anterior horn of the spinal cord into the anterior rootlets and then into the anterior root then into the spinal nerve?
Motor
In which root (anterior or posterior) would you find a ganglion?
Posterior
Within what spinal nerve segment is the male nipple located?
T4
Within what spinal nerve segment is the umbilicus located?
T10
What is a nerve plexus?
A network of intertwined anterior rami
What makes up the cervical plexus?
C1 - C4 anterior rami
What makes up the brachial plexus?
C5 - T1 anterior rami
What does the cervical plexus innervate?
Posterior scalp, neck wall and diaphragm
What does the brachial plexus innervate?
Upper limb
What makes up the lumbar plexus?
L1 - L4 anterior rami
What does the lumbar plexus supply?
Lower limb
What makes up the sacral plexus?
L5 - S4 anterior rami
What does the sacral plexus supply?
Lower limb, gluteal region and perineum
What is a dermatome?
The area of skin supplied by both the anterior and posterior ramus of that spinal nerve
What is a myotome?
The skeletal muscles supplied with motor innervation by both anterior and posterior ramus of that spinal nerve.
Where do sympathetic nerves exit the spinal cord?
T1 - L2
What segments of the spinal cord have lateral horns?
T1 - L2
What is the lateral horn for in the spinal cord?
For cell bodies of sympathetic neurones
Where do the presynaptic axons giving sympathetic innervation to the heart synapse?
T1 (cervical paravertebral ganglia)
How do postsynaptic axons get to the heart?
Pass in cardiopulmonary splanchnic nerves
Where do the presynaptic axons giving sympathetic innervation to the lungs synapse?
upper thoracic paravertebral ganglia
How do postsynaptic axons get to the lungs?
Pass in cardiopulmonary splanchnic nerves
Where do the presynaptic axons giving sympathetic innervation to the foregut synapse?
celiac ganglion of celiac plexus
Where do the presynaptic axons giving sympathetic innervation to the kidney synapse?
aorticorenal ganglion
Where do the presynaptic axons giving sympathetic innervation to the midgut synapse?
superior mesenteric ganglion of SM plexus
Where do the presynaptic axons giving sympathetic innervation to the hindgut synapse?
Inferior mesenteric ganglion of IF plexus
Where do presynaptic axons going to supply the adrenal medulla synapse?
On the adrenaline secreting cells of the adrenal medulla
How do all presynaptic parasympathetic axons leave the CNS
Cranial nerves III, VII, IX & X
Sacral spinal nerves
(Craniosacral outflow)
