03a: CNS Overview and CNs

Question 1

List the divisions of the brain, from rostral to caudal

Answer 1

1. Telencephalon
2. Diencephalon
3. Mesencephalon
4. Metencephalon
5. Myelencephalon

Question 2

The caudal myelenecephalon is (smaller/larger) than SC. The rostral myelencephalon has (X) on its (anterior/posterior/lateral) aspect to add to its size.

Answer 2

Same size;
X = inferior olivary nucleus
Lateral

Question 3

(Rostral/caudal) (X) brain division contains The Pyramids, which are (ventral/lateral/dorsal) bundles of (Y).

Answer 3

Both rostral and caudal;
X = myelencephalon
Ventral;
Y = white matter

Question 4

The metencephalon consists of:

Answer 4

Pons and Cerebellum

Question 5

Caudal mesencephalon consists of:

Answer 5

Inferior colliculus

Question 6

Rostral mesencephalon consists of:

Answer 6

Superior colliculus

Question 7

Which brain division contains the cerebral peduncles?

Answer 7

Mesencephalon

Question 8

Roof of mesencephalon collectively called (X) and floor formally called (Y).

Answer 8

X = tectum
Y = tegmentum

Question 9

Diencephalon consists of:

Answer 9

Thalamus and hypothalamus

Question 10

Telencephalon consists of:

Answer 10

Cerebrum, basal ganglia, hippocampus, amygdala

Question 11

Location of CSF travel in telencephalon.

Answer 11

Lateral ventricles

Question 12

Location of CSF travel in diencephalon.

Answer 12

Third ventricle

Question 13

Location of CSF travel in mesencephalon.

Answer 13

Cerebral aqueduct

Question 14

Location of CSF travel in met encephalon.

Answer 14

Fourth ventricle

Question 15

Location of CSF travel in myelencephalon.

Answer 15

Central canal (of SC)

Question 16

The neural tube gives rise to:

Answer 16

CNS (Brain and SC)

Question 17

During development, cells that don’t join neural crest cell cluster, but remain in surface (X) layer, are formally called (Y).

Answer 17

X = ectoderm
Y = the ectodermal placodes

Question 18

Sensory and motor ganglia of PNS arise from (neural crest/placodes).

Answer 18

Neural crest

Question 19

Schwann cells arise from (neural crest/placodes).

Answer 19

Neural crest

Question 20

Inner ear arises from (neural crest/placodes).

Answer 20

Placodes

Question 21

Chromaffin cells of (X) structure arise from (neural crest/placodes).

Answer 21

X = adrenal medulla

Neural crest

Question 22

Nasal cavities arise from (neural crest/placodes).

Answer 22

Placodes

Question 23

Neuromesenchyme of brachial arches arises from (neural crest/placodes).

Answer 23

Neural crest

Question 24

Neuromesenchyme of pharyngeal arches arises from (neural crest/placodes).

Answer 24

Neural crest

Question 25

Adenohypophysis, aka (X), arises from (neural crest/placodes).

Answer 25

X = anterior pituitary gland | Placodes

Question 26

DRG arise from (neural crest/placodes).

Answer 26

Neural crest

Question 27

Ganglia of CNs arise from (neural crest/placodes).

Answer 27

Both (party from neural crest, partly from placodes)

Question 28

T/F: It's common for some propioceptive fibers in CNs to have cell bodies in midbrain, rather than in sensory ganglion.

Answer 28

False - rare exception in CN V

Question 29

Motor ganglia in H/N can be classified according to their (X). List these categories.

Answer 29

X = location; 1. Paravertebral 2. Terminal 3. Parasympathetic motor ganglia

Question 30

T/F: There are no prevertebral sympathetic ganglia in head/neck.

Answer 30

True

Question 31

Preganglionic sympathetic outflow to head/neck primarily from neurons located in:

Answer 31

T1-T5 SC segments

Question 32

Preganglionic sympathetic outflow to head/neck travel via (X) and synapse on (Y).

Answer 32

``` X = white rami communicantes (then up sympathetic chain) Y = Superior, middle, inferior cervical sympathetic ganglia ```

Question 33

Post-ganglionic sympathetic axons to head/neck can be distributed as:

Answer 33

1. Cervical spinal nerves 2. Branches to some CNs and meninges 3. Branches to cervical viscera and heart 4. Plexuses on arteries (carotid, subclavian, vertebral)

Question 34

True "terminal" parasympathetic ganglion cells occur in:

Answer 34

Tongue, trachea, larynx, lower esophagus

Question 35

Parasympathetic motor innervation of head/neck: Where are the preganglionic cell bodies?

Answer 35

Brainstem (scattered nerve nuclei)

Question 36

Parasympathetic motor innervation of head/neck: What do the preganglionic axons travel in?

Answer 36

CN 3, 7, 9, 10

Question 37

List the "discrete" parasympathetic ganglia in head. List the CN that serves as a PATHWAY for each.

Answer 37

1. Ciliary (V1) 2. Pterygopalatine (V2) 3. Otic (V3) 4. Submandibular (V3)

Question 38

Which sensory info is carried by GSA fibers?

Answer 38

1. Exteroception 2. Propioception 3. General sensation

Question 39

General sensation in head/neck is carried by (X) fibers from (Y) structures by (Z) nerves.

Answer 39

``` X = GSA Y = viscera Z = CN 9 and 10 ```

Question 40

General sensation is (well/poorly) localized.

Answer 40

Poorly

Question 41

(X) neuron modalities mediate interoception.

Answer 41

X = GVA

Question 42

Which CNs carry GVA fibers?

Answer 42

7, 9, 10

Question 43

GVA fibers can carry which type of sensory information? Next to each type, include if it retraces path followed by sympathetic/parasympathetic fibers. Star those that reach level of consciousness.

Answer 43

1. Pain info (sympathetic)* | 2. Physiological reflexes (parasympathetic)

Question 44

SA fibers are found in which CN?

Answer 44

1, 2, 7, 8, 9, 10

Question 45

SVE fibers are found in which CN?

Answer 45

5, 7, 9, 10, 11

Question 46

(X) muscles develop from first pharyngeal arch and are innervated by CN (Y).

Answer 46

``` X = mastication Y = 5 ```

Question 47

(X) muscles develop from second pharyngeal arch and are innervated by CN (Y).

Answer 47

``` X = facial expression Y = 7 ```

Question 48

(X) muscles develop from third pharyngeal arch and are innervated by CN (Y).

Answer 48

``` X = stylopharyngeus (longitudinal muscle of pharynx) Y = 9 ```

Question 49

(X) muscles develop from fourth and sixth pharyngeal arch and are innervated by CN (Y).

Answer 49

``` X = soft palate, pharynx, larynx Y = 10 ```

Question 50

Great vein of Galen drains into (X) sinus

Answer 50

X = straight