Module 12

Question 0

Do spinal nerves have motor or sensory neurons?

Answer 0

*TRICK QUESTION**

Both; sensory and motor

Question 1

What do the spinal nerves do?

Answer 1

Innervate trunk and limbs

Question 2

Which type of nerves do the spinal roots serve?

Answer 2

Dorsal roots: afferents
Cell body in dorsal root ganglia

Ventral roots: efferents
Cell body in ventral root ganglia

Question 3

What type of neuron does the dorsal roots have?

Answer 3

Unipolar

Question 4

What type of neuron does the ventral roots have?

Answer 4

Multipolar

Question 5

Do the ipsilateral spinal roots form the spinal nerves?

Answer 5

Yes!!!

Question 6

What do all spinal nerves supply?

Answer 6

Sensory innervation for skin segments

Question 7

What do lesions to a single spinal nerve cause?

Answer 7

Nothing

Question 8

Does a numerous amount of spinal damage nerves cause problems?

Answer 8

Helps to determine the level of the lesion

Question 9

What comprises the peripheral parts of the SC?

Answer 9

White matter

Question 10

How is the gray matter divided in the SC?

Answer 10

Horizontal plane:

I-VI- dorsal horn

VII- lateral horn

VIII- XI- ventral horn

Question 11

How are the matter tracts oriented on the SC?

Answer 11

Vertically

Question 12

What do the lateral, anterior and posterior funiculi contain?

Answer 12

Lateral- sensory and motor pathways
Anterior- motor
Posterior- sensory

Question 13

Name the 2 types of motor neurons?

Answer 13

Alpha motor neurons (somatic)

GAMMA motor neurons (somatic)

Question 14

What two fibers are in skeletal muscles?

Answer 14

Extrafusal (muscle fibers)- make up mass; innervated by ALPHA motor neurons
Infrafusal- part of muscle spindle; innervated by GAMMA motor neurons

Question 15

Where are interneurons located?

Answer 15

In the gray matter of the SC

Question 16

What is the function of the interneurons ?

Answer 16

Innervated anterior motor neurons

InterGRATIVE role in motor behavior

Question 17

What terminates on the interneurons?

Answer 17

Incoming sensory neurons

Outgoing efferent neurons

Question 18

What are the roles of the muscle receptors?

Answer 18

Excitation of the muscle by the alpha (anterior) motor neurons

Continuous feedback of info from the muscle (length, tension, rate of length/tension)

Question 19

Name the two special sensory receptors?

Answer 19

Muscle spindle

The Golgi tendon organ

Question 20

What does proprioceptors allow us to do?

Answer 20

Sense position

Sense movement of head, jaws, limbs, trunk

Question 21

What kind of receptor is the muscle spindle?

What does it do?

Answer 21

Stretch receptor

Monitors the rate of change of the muscle length and the muscle length itself

Question 22

Name the types of intradusal fiber of the muscle spinal?

Answer 22

Nuclear chain

Nuclear bag

Question 23

What is the capsule of the spindle continuous with?

Answer 23

Tendon of the muscle

Question 24

Where is the nuclei of the intrafusal fiber concentrated?

Answer 24

Middle of the fiber

Question 25

Are type Ia sensory fibers slow or fast conduction?

Answer 25

Fast conducting

Question 26

What are the sensory endings that wrap around the intrafusal fibers?

Answer 26

Primary -annulospinal | Secondary -flower spray ending

Question 27

What does the annulospiral (primary ending) innervate?

Answer 27

Nuclear bag/ chain

Question 28

What does the secondary (flower spray ending) innervate?

Answer 28

The nuclear chain intrafusal ONLY

Question 29

What does the static response of the muscle spindle do?

Answer 29

Responds to: Length/ stretch Have primary/ secondary ending response Response lasts for duration of stretch Response from nuclear chain( Ia/II afferents)

Question 30

What does the dynamic response of the muscle spindle do?

Answer 30

Monitors rate of change Only primary ending responds Response from nuclear bag

Question 31

What's the role of the gamma motor neuron?

Answer 31

Refine/ damping movements (BG/cerebellum/cortex) Regulate spindle sensitivity

Question 32

What's the role of the alpha motor neurons?

Answer 32

Effect voluntary movements Inputs from area 4/3-1-2

Question 33

What does the Golgi tendon organ respond to?

Answer 33

Muscle tension and rate of change

Question 34

What does the static response of the GTO ( Golgi) do?

Answer 34

Steady muscle tension | Steady firing

Question 35

What does the dynamic response of the GTO (Golgi) do?

Answer 35

Suddenly increases tension | Increase in firing

Question 36

Name the 2 types of intrafusal fibers?

Answer 36

Nuclear chain | Nuclear bag