spinal cord

Question 1

The spinal cord extends from the foreman magnum to what vertebra ?

Answer 1

foreman magnum to L1

Question 2

What are the three functions of the spinal cord ?

Answer 2

Conduction , passes info up and down the spinal
Locomotion, repetitive actions of muscle groups
Reflexes, involuntary responses to stimuli

Question 3

What are central pattern generators?

Answer 3

Pools of neurons providing control of flexors and extensors EX. like walking

Question 4

How many pairs of spinal nerves arise from C, L, T and sacral regions of the cord ?

Answer 4

31

Question 5

Where do the nerves that control the upper limbs arise and what is this enlargement called ?

Answer 5

C4-T1 are cervical and control upper limbs , the enlargement is the cervical enlargement and is the whole cervical region.

Question 6

Where do the nerves that control the lower limbs and pelvic?

Answer 6

T9-T12 are pelvic and lower limbs , the enlargement is called the lumbar enlargement and is before the lumbar region.

Question 7

define medullary cone

Answer 7

Taper of the distal cord

Question 8

define cauda equina

Answer 8

“horse tail” bundles of nerves originating form the lumbar enlargement and the medullary cone .

Question 9

What vertebra make up the cauda equina?

Answer 9

L2-L5

Question 10

Define terminal filum

Answer 10

fibrous continuation of the cord beyond the medullary cone. consists of pia matter and neuroglia elements.

Question 11

Where is epidural anesthesia utilized during childbirth?

Answer 11

In the epidural space that is filled with fat and blood vessels

Question 12

What anchors the cord to the coccyx ?

Answer 12

filum terminale and denticulate ligaments

Question 13

Define denticulate ligaments

Answer 13

extension of the pia that extends through the arachnoid to the dura.

Question 14

What does the denticulate ligament do?

Answer 14

suspends the spinal cord in the dural sheath.

Question 15

What is spinabifida ?

Answer 15

Failure of vertebral arch to close covering spinalcord affects one in a thousand babies.

Question 16

What are the two froms of spina bifida?

Answer 16

spinabifida occulta and spinabifida
manifesta
.

Question 17

Dorsal root of spinal nerve is totally what kind of fibers

Answer 17

Sensory nerves

Question 18

Ventral roots of the spinal nerve is totally what kind of fibers?

Answer 18

Motor nerves

Question 19

What is white matter in the spinal column ? What two names is assigned to the white matter ?

Answer 19

The white matter is called White columns or funiculi , they are bundles of myelinated axons that carry signals up & down the cord​

Question 20

What are the symptoms of spina bifida ?

Answer 20

Bowel and bladder control , ADD, and learning disabilities

Question 21

Define Coccygeal ligament

Answer 21

fused terminal filum and dura that anchors the cord and meninges to Co1

Question 22

Explain spina bifida occulta

Answer 22

Hidden , the most mildest form , most children with occulta wont have health problems and the cord is unaffected

Question 23

Explain spina bifida Myelomeningocele

Answer 23

Most severe form, occurs when the meninges and spinal cord push through a hole in the back . Typically will have some sort of paralysis and hydrocephalies” accumulation of fluid in and around the brain”.

Question 24

How is spina bifida diagnosed

Answer 24

Test between 16-18 week of pregnancy. They measure the amount of Alpha-fetoprotein that the fetus produces. They check through ultrasound, or aminocentesis

Question 25

Define decussation

Answer 25

Fibers cross sides

Question 26

How many pathways do the motor neurons have ?

Answer 26

two pathways

Question 27

How many pathways do the sensory neurons have ?

Answer 27

Three pathways, they must go through the thalamus to get to the central gyrus

Question 28

What are the three ascending pathways of sensory neurons?

Answer 28

1st order, detect signal and sends to cord. 2nd spinal cord to thalamus "main sensory relay center" 3rd Thalamus to sensory "Precenteral gyrus"

Question 29

What are the three types of sensory input from the body?​

Answer 29

Discriminative touch, pain and temp, and proprioception

Question 30

Explain Discriminative touch

Answer 30

touch, pressure, and vibration perception. Allows us to see 3-D EX. seeing a cube, not a square

Question 31

Explain Pain and temperature touch

Answer 31

what it sounds like and including itch, and tickle

Question 32

Explain proprioception touch

Answer 32

muscle stretch, joint position, and tendon tension .

Question 33

Where does discriminative touch system cross ?

Answer 33

medulla (spinal cord)

Question 34

Where does the pain system cross?

Answer 34

low spinal cord

Question 35

Where does the proprioception cross?

Answer 35

It doesn't , It works with the cerebellum , which is ipsilateral

Question 36

Where does the Fasiculus gracilis and cuneatus carry signals ?

Answer 36

legs and arms

Question 37

The decussation of second order neurons occurs where ?

Answer 37

cuneate nucleus , in medulla

Question 38

What are upper motor neurons?

Answer 38

begins at soma in cerebral cortex and terminates at the lower neuron

Question 39

What are lower motor neuron?

Answer 39

Large neurons in the ventral horns that send their axons out via spinal roots and directly control the muscles.

Question 40

What percent of the lateral corticospinal decussate in the medulla ?

Answer 40

90%

Question 41

What percent of the ventral corticospinal decussate at the spinal segment?

Answer 41

10%

Question 42

Descending tracts are divided into what two types of tracts?

Answer 42

Pyramidal tracts and extrapyramidal

Question 43

In the category of pyramidal tracts what are corticospinal tracts ?

Answer 43

They carry signals for precise , coordinated, limb movements . They form ridges called pyramids.

Question 44

In the category of pyramidal tracts what are corticobulbar tracts?

Answer 44

axons that intervate the muscles of the face

Question 45

What are extrapyramidal tracts ?

Answer 45

All other motor components , influences the activity of the pyramidal system , exerts its effects on voluntary movement.

Question 46

What are the three extrapyramidal tracks?

Answer 46

Tectospinal, Reticulospinal, & vestibulospinal Tracts

Question 47

Explain the Tectospinal Tract.

Answer 47

Found in the cervical cord only, controls movement of head

Question 48

Explain the Reticulospinal Tract.

Answer 48

Controls movement of limbs for posture & balance

Question 49

Explain the Vestibulospinal Tract.

Answer 49

What Balance & posture (Inner ear signals)

Question 50

What cuases poliomyelitis ?

Answer 50

Fecal contaminated water, causes paralysis & respiratory arrest

Question 51

What is ALS (Amyotrophic lateral sclerosis)?

Answer 51

Degeneration of motor neurons & sclerosis of spinal cord due to astrocyte failure. Causes paralysis & muscle atrophy

Question 52

What surrounds each nerve fiber?

Answer 52

Endonerium

Question 53

What encases nerve bundles?

Answer 53

Perineurium

Question 54

What encases the nerve as a whole?

Answer 54

HEpineurium

Question 55

True or False. Blood vessels penetrate only to the perineurium ?

Answer 55

True

Question 56

How many pairs of spinal nerves are there?

Answer 56

31

Question 57

What do Dorsal ramus supply?

Answer 57

Dorsal body, muscle, & skin

Question 58

What do Ventral ramus supply?

Answer 58

Ventral Skin, Muscles, & limbs

Question 59

What do meningeal branches supply?

Answer 59

Meninges, Vertebrae, and ligaments

Question 60

What are shingles? What are the symptoms?

Answer 60

Reactivation of the herpes Zoster Virus | Skin erupts along path or nerve (Dermatome)

Question 61

True or False. Varicella-Zoster virus (chicken pox) remains for life in dorsal root ganglia?

Answer 61

True

Question 62

What are Dermatomes?

Answer 62

Areas on the skin supplied by sensory fibers of spinal nerves.

Question 63

True or False. Dermatomes overlap each other by 50%?

Answer 63

True, require numbing to more than one nerve in order to numb the whole area

Question 64

What are the four important properties for reflexes?

Answer 64

Reflexes require stimulation, reflexes are quick, reflexes are involuntary, & reflexes are stereotyped (occur the same way every time).

Question 65

What are the 5 steps of a somatic reflex ?

Answer 65

1. stimulation of somatic receptors 2. afferent fibers carry signal to dorsal horn of spinal cord 3. interneurons integrate the info 4. efferent fibers carry info to skeletal muscles 5. skeletal muscles respond

Question 66

What kind of proprioceptor is the muscle spindle?

Answer 66

Stretch receptor that responds to prolonged or onset stretch, wrapped with afferent fibers

Question 67

What do the primary, secondary, & gamma motor fibers respond to?

Answer 67

Primary- muscle stretch Secondary- prolonged stretch Gama motor neuron- Twists the muscle spindle to shorten slack

Question 68

What helps muscles from working against each other?

Answer 68

Reciprocal inhibition

Question 69

Define Golgi tendon organ.

Answer 69

Stretch receptors located within the tendons, they don't respond to length but to how hard it is pulling. By producing inhibitory (Glycine) potentials. Decreases muscle contraction and prevents muscle injury

Question 70

Define spinal shock

Answer 70

Loss of sensation & motor paralyses but gradual recovery of reflexes