Exam 2

Question 1

Describe the gross anatomy of the spinal cord

Answer 1

Long and thin - up to 100 million neurons

43 cm long

1.3 cm diameter

Question 2

At what section is the cord at its largest diameter?

Answer 2

C5-C6 area (Cervical Enlargment)

Question 3

What are the Superior and Inferior boundries of the Spinal Cord?

Answer 3

Superior - Foramen Magnum or C1 Ventral Rootlet

Inferior - Disc between L1 and L2, Conus Medullaris

Question 4

How many pairs of spinal nerves are there? What are each pair made up of?

Answer 4

31 pairs

Dorsal and Ventral roots (rootlets)

Question 5

What does the Bell Magendi law state?

Answer 5

Dorsal roots = sensory

Ventral roots = Motor

Question 6

Are rootlets, spinal nerves and their rami CNS or PNS structures?

Answer 6

PNS!!! ONLY the spinal cord it self and brain are CNS

Question 7

Difference between Roots and Rami?

Answer 7

Rami are branches off of the roots??

Question 8

How are the nerves named? (C1 C2 nerves etc.)

Answer 8

Cervical Nerves are named for the bone below.

Other nerves are named by bone above.

Question 9

Where is the C1 nerve located at?

Answer 9

Between Occiput and Atlas

Question 10

Where is the C4 nerve located?

Answer 10

Between C3 and C4 vertebrae

Question 11

WHere is the C8 Nerve located?

Answer 11

Between C7 and T1 Vertebrae

Question 12

Where is T6 nerve located?

Answer 12

Between T6 and T7 vertebrae

Question 13

Where is T1 nerve located?

Answer 13

Between T1 and T2 vertebrae

Question 14

Where is T12 nerve?

Answer 14

Between T12 and L1 Vertebrae

Question 15

Where do the S1 - S4 nerves exit? S5?

Answer 15

S1-4 exit the dorsal and ventral sacral foramina

S5 exits the Sacral hiatus

Question 16

Where does the Coccygeal nerve Co1 exit?

Answer 16

Sacral hiatus (nerve may be missing)

Question 17

Describe the cord level and vertebral level during the first 3 months of development embryonically.

At birth?

adulthood?

Answer 17

Same length

Birth - Cord level is at L1-L3

Adult - L1 to L2 and taper into conus medullar is

Question 18

The roots for the lumbar, sacral, and coccygeal nerves run for an extended distance below the cord through what structure? WHat is the name for this group of nerves?

Answer 18

Lumbar Cistern

Cauda equina

Question 19

Cord and Vertebral levels are about the same until which level?

Answer 19

L1

Question 20

Name for the tiny and insignificant channel near the center of the spinal cord? Goes from the 4th ventricle to the end of cord. It expands inferiorly in the conus medullaris as a terminal ventricle.

Answer 20

Central Canal

Question 21

Difference between Terminal Ventricle and Lumbar Cistern

Answer 21

Terminal Ventricle is located between T11ish to L1-2 and Lumbar sister goes from L1-2 down to S2.

Question 22

Diagrams page 62 and Page 61`

Answer 22

LEarn them!

Question 23

Describe the three aspects of the Gray matter gross structure (Substantia Grisea) and where they located.

Answer 23

Dorsal horns - located everywhere, sensory

Lateral horns - T1 to L2 and S2 to S4, preganglionic autonomic cell bodies.

Ventral Horns - everywhere, motor

Question 24

Describe Gross structure of white matter (substantial alba)

Answer 24

made up of funicular or white columns

Question 25

What is the name for a longitudinal bundle of white matter fibers

Answer 25

funiculus

Question 26

What are the 4 main microanatomical components of gray matter?

Answer 26

Dence conc. of cell bodies thick dendritic mats near bodies support glial cells dense capillary beds

Question 27

Which of the rexid laminae are sensory?

Answer 27

1-6

Question 28

Lamina 1

Answer 28

Thin cap over posterior horn

Question 29

Lamina 2

Answer 29

Pain reception Supstantia Gelatinosa

Question 30

Lamina 3 and 4

Answer 30

Nucleus Proprius

Question 31

Lamina 5

Answer 31

Formatio Reticularis found on lateral portion in CERVICALS only.

Question 32

Lamina 6

Answer 32

Missing at some levels, Most anterior portion of the dorsal horn

Question 33

Lamina 7

Answer 33

Intermidate gray area, lateral horn included when present Nucleus Dorsalis (Clarkes Nucleus) C8 - L3 contributes to Posterior Spinocerebellar Intermediolateral nucleus**

Question 34

Describe intermediolateral nucleus

Answer 34

Found in lamina 7 forms the bulk of lateral horn cell bodies at T1-T12 Appears without a distinct horn at L1,L2, and S234 They are the Autonomic motor neurons known as Preganglionic sympathetic neurons (T1-L2) Preganglionic parasympathetic neurons. (S2,3,4)

Question 35

Lamina 8

Answer 35

Medial aspect of anterior ventral horn

Question 36

Lamina 9

Answer 36

Class A alpha motor neuron islands

Question 37

Lamina 10

Answer 37

surrounds central canal and contains anterior posterior gray comissures

Question 38

Know diagram on 68 by heart!!!

Answer 38

KNow it

Question 39

Upper and Lower motor neurons

Answer 39

Lower - originate in cord or brainstem and extend to PNS to innervate somatic muscle Upper - originate in higher brain centers that influence lower motor neurons. (corticospinal tract fibers are good examples)

Question 40

Upper motor neuron lesion signs

Answer 40

Reduction/absence of voluntary movement Hyperreflexia increased muscle tone clonus Babinski sign Cerebral palsy example

Question 41

Lower Motor Neuron lesion signs

Answer 41

reduction/absence of voluntary movement hyporeflexia or areflexia decreased muscled tone and atrophy muscle fibrilliations polio

Question 42

Pyramidal vs Extrapyramidal neurons

Answer 42

Pyramidal - UMN involved with initiation of voluntary movements Extrapyramidal - UMN complex that influences posture, tone, enhance reflexes, allow smooth and effective movments.

Question 43

Corticospinal tracts have which type of neurons in them? Tecto, Rubro, and Vestibulospinal tracts have which type of neurons in them?

Answer 43

Pyramidal neurons Extrapyramidal fibers

Question 44

Name for total loss of either right or left side of spinal cord (hemisection)

Answer 44

Brown-Sequrad Syndrome

Question 45

Destruction of CNS myelin only common in females more, onset ages 20-40

Answer 45

Multiple Sclerosis

Question 46

Destruction of UMN and LMNs mainly in Lateral Corticospinal tracts common in males onset after age 45

Answer 46

Amyotrophic Lateral Sclerosis

Question 47

Name for Hindbrain

Answer 47

Rhombencephalon

Question 48

Parts of hindbrain

Answer 48

Medulla Oblongata Pons Cerebellum

Question 49

Which portion of the rhombencephalon is part of the myelencephalon? which are part of the metaencephalon? Brainstem?

Answer 49

Medulla Oblongta Pons and Cerebellum Midbrain, Pons, M.O, NOT CEREBELLUM

Question 50

Where cranial nerve appears to be attached to the surface of the CNS

Answer 50

Apparent origin

Question 51

The nucleus or nuclei that contribute MOTOR fibers to the cranial nerves. Located inside of CNS

Answer 51

Nucleus of origin

Question 52

The nucleus or nuclei that receive incoming afferent SENSORY input from cranial nerves, located inside CNS

Answer 52

Nucleus of Termination

Question 53

3 Functions of Medulla Oblongata

Answer 53

Passive fiber conduction relay nuclei: gracilis, cuneatus, olive C.N. Nuclei - 5,7,8,9,10,11,12 Resp and cardiac function, swallowing

Question 54

Medulla oblongata location

Answer 54

most inferior part of the rhombenecephalon and the brain stem

Question 55

The Medulla Oblongata is ventral to the... Inferior to the ... Superior to the... Where is the exact inferior border of it?

Answer 55

Cerebellum (4th ventrcile) Pons Spinal Cord Superior most C1 Rootlet

Question 56

External features of the Medulla Oblongata Learn Page 94 list for diagram!

Answer 56

All the sulci and rhomboid fossa apparent origins of cn nerves olive (inferior olivary nucleus) pyramids (decussation fibers also) Obex and area postrema DIAGRAM!!!

Question 57

Internal features of the MEdulla oblongata Learn figure on page 95

Answer 57

Inferior Olivary Nucleus Reticular Formation Pyramids Medial Lemniscus

Question 58

Apparent origin of cranial nerves 9 10 and 11

Answer 58

near the posterolateral sulcus

Question 59

Apparent origin of cranial nerve 6

Answer 59

in the inferior pontine sulcus

Question 60

apparent origin of cranial nerve 7 and 8

Answer 60

in the pontocerebellar angle

Question 61

apparent origin of cranial nerve 12

Answer 61

in the ventrolateral sulcus

Question 62

Which fibers are located in the pyramids? Which fibers cross (decussate) in the pyramids?

Answer 62

corticospinal fibers Lateral corticospinal tract

Question 63

What are the important brainstem nuclei?

Answer 63

Edinger-Westphal nucleus (Acessory Oculomotor) Dorsal Nucleus of Vagus Nucleus Ambiguus Nucleus Solitarius Spinal Trigeminal Nucleus