Quiz 3: Lecture 7-8 Nervous System Flashcards
What is the Central Nervous System? What structures are apart of it?
The central nervous system
- Brain
- Spinal Cord
The PNS is broken into two subdivisions. Name them and their function.
Somatic and Autonomic
Somatic (voluntary):
- Sensation from skin and joints
- Motor to skeletal muscle
Autonomic (involuntary):
- Sensation and motor to smooth muscle cardiac muscle, and glands
The autonomic division of the PNS is broken into 2 subdivisions. What are they?
Parasympathetic and Sympathetic
What does the parasympathetic division of the autonomic nervous system do?
- Responsible for “rest and digest”
- Vagus and pelvic splanchnic nerves provide parasympathetic innervation
- Synapses on the organ wall
- DOES NOT USE SYMPATHETIC CHAIN
The vagus nerve provides parasympathetic innervation to which organs + regions?
Heart, lungs, foregut, midgut
The pelvic splanchnic nerves originate where? What does it innervate?
- S2-S4
- innervates the hindgut
What does the sympathetic division of the autonomic nervous system do?
- Responsible for “fight or flight”
- Synapses in sympathetic chain (short preganglionic, long postganglionic)
What do sensory receptors do?
Brings info to the CNS
Explain the somatic nervous system
Voluntarily controls skeletal muscle movement
What does afferent mean?
Sensory (ascending signal sending information to the brain)
What does efferent mean?
Motor (descending signal telling something in the body what to do)
Dorsal horn/rami is for what type of signals
Sensory signals (somatic)
Lateral horn is used for what type of signals?
Used for autonomic nervous system signals
What is the ventral horn/rami used for?
Motor signals (somatic)
Which structures are made of grey matter?
Spinal cord, cerebral and cerebellar cortex, neuronal cell bodies
What is another name for the sympathetic chain?
Paravertebral ganglia or sympathetic trunk
What is a ganglia/ganglion?
Cluster of cell bodies found throughout the body
What is an ascending pathway? How many neurons does it have?
Ascending pathways are used for sensory signals, and have a chain of 3 neurons
What is a descending pathway? How many neurons?
Deliver motor instructions from brain to the spinal cord. Also has a chain of 2 neurons
Where does nerve c1 emerge from the spinal cord?
Between the skull and c1 vertebra
Where do nerves C2 to C7 emerge from spinal cord?
Superior to pedicles of their respective vertebrae
Where does the 8th cervical nerve emerge from the spinal cord?
Below C7
Where do T1 nerve and inferior nerves emerge from the spinal cord?
Inferior to the pedicle of their respective vertebrae
What is a synapse?
When one neuron transfers a signal to another neuron
Visceral sensation comes from __________________ fibers
Parasympathetic
Visceral pain comes from ________________ fibers
Sympathetic
What is the purpose of the white ramus/rami?
Brings preganglionic neurons to the sympathetic chain from the spinal nerve
What is the purpose of grey ramus/rami?
Brings postganglionic neurons from the sympathetic chain back to the spinal nerve
The dorsal root and ventral root connect to make the _________ nerve
Spinal
Which root has a ganglion? Dorsal or Ventral?
Dorsal
Why is there a lumbar and cervical enlargement in the spinal cord?
Because there are a lot more motor and sensory neurons to control those areas (arms and legs)
Where does the spinal cord end? What is that place called?
L1/L2 (called the conus medullaris)
What is the group of nerves called that exits the spinal cord and begin to branch off from one another?
Cauda Equina
What is the filum terminale?
Covering of the spinal cord that extends all the way down to the coccyx
What are meninges? What are the layers?
Layers that surround the spinal cord for protection
- outermost layer: dura mater
- middle layer: arachnoid mater
- innermost layer: pia mater
What do denticulate ligaments do?
Provide lateral support that connects to the dura layering of spinal cord
What is the blood supply to the spinal cord?
- 1 Anterior spinal artery (from both the vertebral arteries)
- 2 posterior spinal arteries (run posterior/lateral)
- segmental spinal arteries (one at every level of vertebra)
Which vessels drain venous blood from the spinal cord?
Subarachnoid veins (3 anterior vessels, 3 posterior vessels)
The spinal cord “floats” in a liquid called…
Cerebrospinal fluid
What do the anterior and posterior rami go to?
Anterior rami: to the lateral and anterior trunk + limbs
Posterior rami: muscles, joints, skin on back
To somatically control the arms or legs, which rami is used?
Ventral rami
To control back muscles, which rami is used?
Dorsal rami
The central nervous system includes all of the following structures except…
Nuclei tracts, spinal cord, brain, ganglia
Ganglia
The division of the nervous system that allows voluntary motor commands is the…
- afferent, sensory receptors
- afferent, somatic
- efferent, somatic
- efferent, autonomic
Efferent, somatic
All of the following statements are false except
- C8 nerve emerges above C7 vertebrae
- C8 nerve emerges below C7 vertebrae
- Cervical nerves emerge below their corresponding vertebrae
- Thoracic nerves emerge above their corresponding vertebrae
C8 nerve emerges below C7 vertebrae
All of the following are true except
- preganglionic neurons innervate cardiac muscle, smooth muscle, and glands
- the autonomic nervous system always has a 2 motor neuron chain
- there is only one somatic motor neuron from the CNS to the skeletal muscle it innervates
- postganglionic cell bodies are located in the autonomic ganglia
Preganglionic neurons innervate cardiac muscle, smooth muscle, and glands
T or F? The thoracolumbar preganglionic cell bodies emerge from the lateral horn of T1-L2
True
Parasympathetic afferent pathways give the CNS information on all of the following except…
- ischemia
- visceral reflexes
- pain from viscera below the pelvic line
- birth canal
Ischemia
The cells bodies of post-ganglionic parasympathetic fibers innervating the heart are located
- In the cardiopulmonary splanchnic nerves
- In the sympathetic ganglia
- Within the vagus nerve
- Within the walls of the heart
Within the walls of the heart
To innervate the lungs, pre-ganglionic sympathetic fibers synapse
- Within the celiac ganglia
- In the walls of the lungs
- In the sympathetic chain
- In the celiac ganglion
In the sympathetic chain
Pre-ganglionic sympathetic fibers that provide innervation to the midgut come from
- Greater splanchnic nerves
- Lesser splanchnic nerves
- Lumbar splanchnic nerves
- Pelvic splanchnic nerves
Lesser Splanchnic Nerves
Pre-ganglionic fibers within the sympathetic chain can
- Ascend or descend within the trunk and synapse
- Synapse at the same level
- Pass through the sympathetic trunk
- All of the above
All of the above
- The innominate bone is made up of thee fused bones which meet at the
- Acetabulum
- Sacrum
- Pubis
- Ischium
Acetabulum
The Levator ani muscles are made up of all of the following except
- Puborectalis
- Coccygeus
- Pubococcygeus
- Illiococcygeus
Coccygeus
- The pudendal artery, with the pudendal nerve exits the ___ foramen and enters again through the ___ foramen.
- Obturator, lesser sciatic
- Greater sciatic, lesser sciatic
- Greater sciatic, obturator
- Lesser sciatic, greater sciatic
Greater Sciatic, Lesser Sciatic
What do white ramus/rami do?
Bring neurons to the sympathetic chain from spinal nerve
What do grey ramus/rami do?
Bring neurons back to the spinal nerve from the sympathetic chain
❗️Where are postganglionic sympathetic cell bodies found? (foregut)
Celiac ganglia
❗️Where are postganglionic sympathetic cell bodies located? (midgut)
Superior mesenteric ganglion
❗️Where are postganglionic sympathetic cell bodies located? (hindgut)
Inferior mesenteric ganglion
Neurons in the dorsal root ganglia…
- provide motor Innervation to skeletal muscle fibers
- provide motor Innervation to viscera
- provide sensory Innervation to skin
- send their axons to the ventral root
Provide sensory Innervation to skin
Which of the following is innervated by the somatic nervous system?
- smooth muscle
- cardiac muscle
- glands
- skeletal muscle
Skeletal muscle
Which of the following is true regarding somatic lower motor neurons?
- cell bodies are located in the ventral horn of the spinal cord
- cell bodies are located in the lateral horn of the spinal cord
- cell bodies are located in the dorsal horn of the spinal cord
- their axons synapse on ganglia close to the muscles they innervate
Cell bodies are located in the ventral horn of the lower spinal cord
What is the function of the parasympathetic division of the autonomic system?
“Rest + Digest”
What is the function of the sympathetic division of the autonomic system?
“Fight or Flight”
How many neurons from the CNS to its destination (somatic)?
1
How many neurons from the CNS to its destination (autonomic)?
2
Grey and white rami are ONLY used when signals are from what system?
Sympathetic
Where are parasympathetic cell bodies located?
T12 - L1 (pelvic splanchnic nerves)
Differentiate between the preganglionic and postganglionic length (parasympathetic / sympathetic)
Parasympathetic:
- long preganglionic
- short postganglionic
Sympathetic:
- short preganglionic
- long postganglionic
_________________ are only from T1-L2 because that is where the sympathetics are
White rami
Where are somatic upper motor neurons found?
Cerebral cortex
Which of the following is true in regard to the autonomic Innervation of the lungs?
- postganglionic sympathetic neuron cell bodies are located in the pulmonary plexus
- preganglionic sympathetic fibers synapse in the celiac ganglion
- postganglionic sympathetic neuron cell bodies are located in the paravertebral ganglion
- postganglionic parasympathetic neuron cell bodies are located in the paravertebral ganglion
- preganglionic sympathetic fibers are carried in the cardiopulmonary splanchnic nerves
postganglionic sympathetic neuron cell bodies are located in the paravertebral ganglion
The paravertebral ganglia contains cell bodies of
- preganglionic sympathetic neurons
- postganglionic sympathetic neurons
- somatic motor neurons
- preganglionic parasympathetic neurons
Postganglionic sympathetic neurons
Which of the following is true regarding the greater splanchnic nerve?
- it contains preganglionic neurons traveling to the celiac ganglia
- it provides parasympathetic Innervation to the foregut
- it contains preganglionic neurons traveling from the celiac ganglia
- it provides parasympathetic Innervation to the midgut
It contains preganglionic neurons traveling to the celiac ganglia
All of the following are true regarding the sympathetic nervous system except
- Preganglionic neurons enter the sympathetic chain via the white rami
- preganglionic neurons are in the lateral horn of the spinal cord from S2-S4
- postganglionic neurons exit the sympathetic chain via the grey rami
- preganglionic neurons are in the lateral horn of the spinal cord from T1 to L2
preganglionic neurons are in the lateral horn of the spinal cord from S2-S4
