Spinal Nerves And Reflexes

Question 1

Spinal reflexes

Answer 1

They are subconscious

Question 2

Spinal cord is divided into

Answer 2

Posterior median sulcus

Anterior median fissure

Question 3

How many cervical nerves 
Thoracic nerves 
Lumbar nerves 
Sacral nerves 
Coccygeal nerves

Answer 3

Cervical 8 
Thoracic 12 
Lumbar 5 
Sacral 5 
Coccygeal 1-2

Question 4

Dorsal roots

Answer 4

Are posterior and are always sensory

Question 5

Ventral roots

Answer 5

Are anterior and are motor and control somatic and visceral effectors

Question 6

Spinal nerve

Answer 6

Mixed nerves sensory and motor

Question 7

Dura Mater

Answer 7

Tough outer layer of spinal cord

Question 8

Three spinal meninges

Answer 8

Dura mater
Arachnoid mater
Pia mater
Protect spinal cord and carry blood supply

Question 9

Arachnoid mater

Answer 9

Middle layer

Question 10

Subdural space

Answer 10

Cerebrospinal fluid

Between dura and arachnoid

Question 11

Pia mater

Answer 11

Inner most layer

Soft and connected to neural tissue

Question 12

Denticulate ligaments

Answer 12

Keeps spinal cord in place

Extends from pia to dura so there is no side to side movement

Question 13

Organization of gray mater

Answer 13

Posterior gray horns
Anterior gray horns
Lateral gray horns

Question 14

Posterior gray horns

Answer 14

Somatic and visceral sensory nuclei

Question 15

Anterior gray horn

Answer 15

Contain somatic motor nuclei

Question 16

Lateral gray horn

Answer 16

Interneuron communication

Question 17

Gray commissures

Answer 17

Connect right and left side of gray matter

Question 18

Organization of white matter

Answer 18

Posterior white columns
Anterior white columns
Lateral white columns

Question 19

Tracts or fasciculi

Answer 19

Bundles of axons relaying info in white matter

Question 20

Ascending tracts

Answer 20

Carry sensory afferent info to brain

Go through the dorsal root

Question 21

Descending tracts

Answer 21

Carry motor commands to spinal cord

Go through central root

Question 22

Three tissue layers of spinal nerves

Answer 22

Epineurium outer layer collagen fibers
Perineurium middle divides nerves into axon bundles
Endoneurium inner surrounds individual axons

Question 23

White ramus

Answer 23

Carries visceral motor fibers to sympathetic ganglion

Question 24

Gray ramus

Answer 24

Returns sympathetic ganglion to rejoin spinal nerve

Question 25

Dorsal ramus

Answer 25

Somatic and visceral to the back

Question 26

Ventral ramus

Answer 26

Goes to the front

Question 27

Dermatomes

Answer 27

Sections of skin supplied by certain spinal nerve

Question 28

Four types of nerve plexuses of ventral rami

Answer 28

Cervical plexus Brachial plexus Lumbar plexus Sacral plexus

Question 29

Phrenic nerve

Answer 29

Controls diaphragm and includes c1- c5 | Cervical plexus

Question 30

Major nerves of brachial plexus

Answer 30

``` Musculocutaneous nerve Median nerve Ulnar nerve Axillary nerve Radical nerve ```

Question 31

Lumbar plexus major nerves

Answer 31

Genitofemoral nerve Lateral femoral cutaneous nerve Femoral nerve

Question 32

Sacral plexus major nerves

Answer 32

Pudendal nerve | Sciatic nerve

Question 33

Organization of neurons

Answer 33

Sensory neurons Motor neurons Interneurons

Question 34

Neuronal pools

Answer 34

Functional groups of interconnected neurons

Question 35

Five patterns of neuronal pools

Answer 35

``` Divergence Convergence Serial processing Parallel processing Reverberation ```

Question 36

Reflex arc

Answer 36

Begins at receptor and ends at peripheral effector

Question 37

5 steps of neural reflex

Answer 37

``` Arrival of stimulus, activation of receptor activation of sensory neuron Info process by postsynaptic ganglion Activation of motor neuron Response of peripheral effector ```

Question 38

Monosynaptic reflex

Answer 38

Sensory neuron synapse directly on motor neuron

Question 39

Polysynaptic reflex

Answer 39

At least one interneuron is between sensory and motor neuron

Question 40

Stretch reflex

Answer 40

Triggered by elongation of tendon | Ex: patellar reflex

Question 41

Intrafusal muscle fibers

Answer 41

Receptors that sense the stretch | In a stretch reflex

Question 42

3 characteristics of polysynaptic reflexes

Answer 42

Involve reciprocal inhibition Involve pools of neurons Several reflexes cooperate

Question 43

Reciprocal inhibition

Answer 43

Motor neurons are stimulated, the neurons that control the opposing muscle are inhibited. This allows one muscle to flex and opposing to relax

Question 44

Golgi tendon organs

Answer 44

Located between skeletal muscle tendon. Dendrites branch and wrap around tendon. Stimulated by tension in tendon. Monitor external tension, when stimulated during contraction it will cause muscle to relax

Question 45

Autonomic reflexes

Answer 45

Involuntary superficial skin and mucous membranes | Stretch or deep tendon reflexes

Question 46

Visceral reflexes

Answer 46

Control systems other than muscular system | Smooth, cardiac, glands, adipose tissue