Chapter 13 - spinal cord + spinal nerves

Question 1

List the meninges and spaces in order from superficial to deep (spinal cord).

Answer 1

epidural space (fat)
dura mater
subdural space (interstitial fluid)
arachnoid mater
subarachnoid space (CSF)
pia mater
spinal cord

Question 2

The spinal cord begins at the level of the ___ as a continuation of the _____.

It terminates at the level of __.

Answer 2

foramen magnum
medulla oblongata

L2

Question 3

The anterior and posterior roots of a spinal nerve are called the ___ and connect the spinal nerve to…

Answer 3

radix

a segment of the spinal cord

Question 4

Once a spinal nerve passes through its intervertebral foramen, the nerve divides into several branches, known as _____. These include:

Answer 4

rami

posterior/dorsal ramus
anterior/ventral ramus
rami communicantes

Question 5

Damage to the spinal cord above ___ causes respiratory failure.

Answer 5

C3

Question 6

The cervical plexus includes the ventral rami of spinal nerve roots from __ to __.

Answer 6

C1-C5

Question 7

The brachial plexus includes ventral rami from spinal roots ___ to ___.

Answer 7

C5-T1

Question 8

The lumbar plexus includes ventral rami from spinal nerve roots __ to ___.

Answer 8

L1 to L4

Question 9

The sacral plexus includes ventral rami of nerve roots __ to __.

Answer 9

L4-S4

Question 10

The sciatic nerve includes roots from __ to ___.

Answer 10

L4-S3

Question 11

What are the ascending (sensory) spinal cord tracts?

Answer 11

> lateral and anterior spinothalamic tracts
anterior and posterior spinocerebellar tract
posterior (dorsal column-medial lemniscus) tract

Question 12

What are the descending (motor) tracts of the spinal cord?

Answer 12

lateral and anterior corticospinal tracts
corticobulbar tracts

rubrospinal, reticulospinal, tectospinal, and vestibulospinal tracts

Question 13

What are the DIRECT (pyramidal) motor tracts of the spinal cord?

Answer 13

lateral and anterior corticospinal, and corticobulbar tracts

Question 14

How does a stretch reflex work?

Answer 14

sudden stretching of one muscle will cause an inhibition (relaxation) of its antagonist and contraction of the muscle itself to prevent overstretching

Question 15

How does a tendon reflex work? (GTO)

Answer 15

Increased tension on a tendon causes the brain to tell the antagonist to contract, and the muscle whose tendon has been suddenly loaded to relax (relieve tension) to prevent tearing/injury.

Question 16

How does the crossed-extensor reflex work?

Answer 16

when flexors of right leg contract, extensors of opposite leg will contract

Question 17

This re-enters the vertebral cavity through the intervertebral foramen and supplies the vertebrae, ligaments, and blood vessels of the spinal cord and meninges.

Answer 17

meningeal branch

Question 18

What pathway governs automatic movements and coordinates them with visual stimuli?

Answer 18

reflex arc

Question 19

How many connections to the spinal cord does a typical spinal nerve have?

Answer 19

2

Question 20

Which is further from the spinal cord: the rami or the roots?

Answer 20

the rami

Question 21

The grey and white rami communicates branch off from the ventral or dorsal ramus?

Answer 21

ventral

Question 22

The rami/roots are mixed (contain both sensory and motor fibres)?

Answer 22

The rami contain both sensory and motor fibres. The roots contain either sensory (dorsal) or motor (ventral) fibres.