Spinal Cord & Spinal Nerve

Question 1

____________: Part of peripheral nervous system taking messages to and from spinal cord. They are mixed, carrying both sensory and motor info

Answer 1

Spinal nerve

Question 2

________: The caudal-most spinal nerves pass caudally together, resembling a horse’s tail, before exiting the appropriate intervertebral foramen.

Answer 2

Cauda equina

Question 3

Overall function of the spinal cord

Answer 3

Carry messages to and from brain, and spinal reflexes.

Question 4

Location of the spinal cord

Answer 4

Vertebral foramen/canal. It runs from foramen magnum to about L2.

Question 5

Significance of two spinal cord enlargements

Answer 5

Arms & legs nerves entering & exiting spinal cord

Question 6

Protective coverings of CNS

Answer 6

General is meninges, specific is dura mater (outermost), arachnoid, then pia mater.

Question 7

Location of CSF

Answer 7

Subarachnoid space

Question 8

Where are anesthetics given?

Answer 8

Epidurals are given outside of the dura mater. L2 or below would be a safe place to administer the anesthetic without hitting the spinal cord.

Question 9

Of the gray matter of the spinal cord, the ______________ receive sensory information and the _____________ transmit motor information. Since it is gray, it would contain neuron cell bodies, and unmyelinated neurons.

Answer 9

Dorsal grey horn

Ventral grey horn

Question 10

___________: Includes the The lateral, dorsal (posterior) and ventral (anterior) columns within the spinal cord

Answer 10

White matter of spinal cord

Question 11

Within the ____________________ are the ascending tracts carrying sensory information toward the brain and the descending tracts carrying motor information away from the brain.

Answer 11

White columns of the spinal cord

Question 12

_________: is a fast repetitive response to a stimulus. It is involuntary i.e. not at the conscious level

Answer 12

Reflex

Question 13

Generalized reflex arc

Answer 13

Stimulus – Receptor – afferent sensory neuron – CNS (spinal cord) – efferent motor neuron – effector (such as a skeletal muscle)

Question 14

One synapse in the spinal cord is _____________ reflex and would be very fast.
Example patellar

Answer 14

Monosynaptic

Question 15

A_________________ has more than one synpase in the spinal cord – thus synapsing on interneurons or association neurons before synapsing on the motor neuron. These are slower reflexes and if they stay ipsilateral may describe the withdrawal reflex and if they go contralateral may describe the crossed extensor reflex.

Answer 15

polysynaptic reflex

Question 16

If you hit the patellar tendon, you stretch the quad. muscle and stimulate the stretch receptor. It is an ______________, ______________reflex ending with the quad. muscle contracting, thus extending the knee.

Answer 16

Ipsilateral

Monosynaptic

Question 17

If you step on the nail, the pathway is the withdrawal reflex resulting in an ipsilateral contraction of your flexors so that you pull away from the nail and a compensatory extension of the contralateral leg so that you can support your weight. This is known as a _________ ____________ reflex

Answer 17

Crossed extensor relfex

Question 18

The spinal nerve has a dorsal root carrying ___________ info into the dorsal gray horn and a ventral root carrying _____________ info exiting the ventral gray horn.

Answer 18

Sensory

Motor

Question 19

After the mixed spinal nerve leaves the vertebra, it branches into a _______ ramus (branch) going toward your back and a _______ ramus going everywhere else in your body, including limbs and viscera.

Answer 19

Dorsal and ventral

Question 20

_________: Network of successive spinal nerves.

Answer 20

Plexus

Question 21

4 main plexuses

Answer 21

Cervical (about C1-4);
Brachial (about C5-T1),
Lumbar (about L1-4)
Sacral (about L4-S4)

Question 22

_________ nerve: originates from Brachial plexus innervates pectoral limb extensors

Answer 22

Radial

Question 23

_________ nerve: originates from Brachial plexus innervates distal medial flexors (e.g. flexor carpi ulnaris)

Answer 23

Ulnar

Question 24

_____________ nerve: originates from Brachial plexus innervates elbow flexors (e.g. biceps brachii)

Answer 24

Musculocutaneous nerve

Question 25

______ nerve: originates from Brachial plexus innervates distal lateral flexors (e.g. flexor carpi radialis)

Answer 25

Median

Question 26

______ nerve: originates from Lumbar plexus innervates hip flexors and knee extensors (e.g. quadriceps)

Answer 26

Femoral

Question 27

__________ nerve: originates from Sacral plexus innervates knee flexors (hamstrings) as well as all distal to your knee.

Answer 27

Sciatic nerve

Question 28

________ nerve: originates from Cervical plexus innervates your diaphragm and needed to breathe!

Answer 28

Phrenic