introduction to the nervous system

Question 1

the nervous system is divided into 2 groups which are?

Answer 1

CNS

Peripheral nervous system

Question 2

the peripheral NS is divided into how many groups? what are their names?

Answer 2

Somatic NS

Autonomic NS

Question 3

the autonomic nervous system us responsible for what? what are its subdivisions?

Answer 3

involuntary control of visceral organs
Parasympathetic NS–> Rest and digestion
Sympathetic NS –> Fight or flight

Question 4

what is the role of the somatic nervous system?

Answer 4

voluntary control of sensory and motor functions

Question 5

area of the skin innervated by a given spinal nerve

Answer 5

dermatome

Question 6

a group of muscles innervated by a given spinal nerve

Answer 6

myotome

Question 7

what nerve plexus is responsible for the upper limbs? where does it range?

Answer 7

brachial plexus

from C5-T1

Question 8

what nerve plexus is responsible for the lower limbs? where does it range?

Answer 8

Lumbosacral Plexus

L1-S4

Question 9

what region is affected near the nipple?

Answer 9

T4

Question 10

what happens if nerve on T6 is affected?

Answer 10

nerves going to the skin above the xiphoid process will be affected

Question 11

what region is covered by T10?

Answer 11

umbilicus

Question 12

why is it clinically significant to understand region of skin innervation?

Answer 12

it enables us to understand certain spinal cord injuries particularly, the level of the injury, if it’s complete or incomplete.

Question 13

what is the conus medullaris?

Answer 13

it is the tapered lower end of the spinal chord. it is at that point the the filum terminale begins.

Question 14

what is the filum terminale

Answer 14

it is the prolongation of the spinal chord. its purpose is to serve as an anchor.

Question 15

what is the causa equina?

Answer 15

it is a bundle of spinal nerves. it begins at L2 and goes all the way down to the very last vertebrae of the coccyx.

Question 16

how does the spinal cord ressemble at the embryo stage?

Answer 16

it fills out the vertebral column

Question 17

Identifiy the stage at which the spinal chord ends

• L3
• L1-L2

Answer 17

birth

adult

Question 18

what do spinal chord enlargments correponds with?

what are the 2 enlargements found on the spinal cord?

Answer 18

they correspond with their respective plexuses.
cervical enlargement with the brachial plexus
lumbar enlargement with the lumbosacral plexus

Question 19

what is the neuron?

Answer 19

it is the basic unit of the NS

Question 20

how do neurons communicate?

Answer 20

through chain-like connections that send electrical impulse to one another.

Question 21

where is the posterior horn identified on the spinal cord?

Answer 21

the posterior horn is found on the gray matter, its the winged shaped structure

Question 22

where is the posterior horn identified on the spinal cord?

Answer 22

the anterior horn is found on the gray matter it is the more rounded structure.

Question 23

what is the gray matter composed of

Answer 23

cell bodies

Question 24

what does the cervical enlargement give rise to?

Answer 24

gives rise to nerves on the upper limbs.

it occurs between C5-T1

Question 25

what does the lumbar enlargement give rise to?

Answer 25

gives rise to the nerves of the lower limbs. | occurs at L1-S4

Question 26

what is the name of the biggest fold in the spinal cord?

Answer 26

anterior median fissure

Question 27

what part of the spinal cord represents the line of attachment between the dorsal and ventral spinal roots

Answer 27

the posteo-lateral Sulcus & the Anterolateral Sulcus

Question 28

what is the white matter composed of?

Answer 28

axon's & myelin

Question 29

what are spinal meninges?

Answer 29

a membrane that surrounds, supports and protect the spinal cord and spinal nerve roots

Question 30

how are the spinal nerves divided

Answer 30

you have the dorsal rootlets- that merge into the dorsal root into the dorsal ganglion (on the posterior side on the anterior side you have ventral rootlets that merge into ventral roots. the dorsal and ventral root merge to form the spinal nerves which divides back into the dorsal ramus and ventral ramus

Question 31

what is the main function of the dorsal rami

Answer 31

responsible for innervation of the skin of the back, intrinsic muscles of the bac

Question 32

what are the 3 Layers of meninges of the spinal cord?

Answer 32

- dura matter - arachnoid matter - pia matter

Question 33

what ligament can be observed through the meninges of the spinal cord at the level of the pia?

Answer 33

denticulate ligaments

Question 34

how would you describe the dura matter?

Answer 34

its can be seen as though matter

Question 35

what meninges matter is described to look cob-web-like?

Answer 35

arachnoid matter

Question 36

what is the pia matter described as? | what can be observed at that depth?

Answer 36

the tender mother | at the same depth we can observe the dendiculate ligament & the filum terminale

Question 37

how does the spinal nerve exit the vertebral column?

Answer 37

the spinal nerve exits through the intervertebral foramen & bifurcates into the ventral and dorsal ramus

Question 38

relative to the cervical vertebrae, where is the cervical spinal nerves located

Answer 38

above the vertebrae

Question 39

how many cervical spinal nerves are there?

Answer 39

8 spinal nerves but only 7 cervical vertebrae

Question 40

where do the spinal nerves for the thoracic and lumbar vertebrae exit?

Answer 40

the exit below the vertebrae

Question 41

where do the sacral spinal nerves exit from?

Answer 41

they exit through the anterior and posterior sacral foramina below the corresponding sacral segments

Question 42

what nerves bring sensory information from periphery to CNS via the dorsal root?

Answer 42

afferent nerves

Question 43

what nerves transmit motor commands from the CNS to the periphery via ventral roots?

Answer 43

efferent nerves

Question 44

what trick is used to recall spinal nerve signaling?

Answer 44

in the Dor(Sal) out the Vent(ral)

Question 45

what is often found in the epidural/extradural space?

Answer 45

fatty tissue

Question 46

what is the space between the dura mater and the pia mater

Answer 46

subdural space

Question 47

what is the subarachnoid space

Answer 47

spinal fluid

Question 48

what is the clinical significance of the meningeal

Answer 48

lumbar tap is executed at the lumbar levels, due to thoracic vertebrae overlap ideally puncture at l4/l5