L3_ Introduction to the nervous system

Question 1

what’s in the central nervous system?

Answer 1

brain and spinal cord

Question 2

what’s in the peripheral system?

Answer 2

all nerves outside of the spinal cord

Question 3

what’s the somatic nervous system?

Answer 3

voluntary control of sensory and motor functions

Question 4

What’s the autonomic nervous system?

Answer 4

involuntary control over visceral organs

Question 5

myotome?

Answer 5

group of muscle innervated by a single spinal nerve

Question 6

dermatome?

Answer 6

area/region of skin innervated by a single spinal nerve

Question 7

What’s the basic trajectory of an information in the nervous system?

Answer 7

1- stimulis from the environment
2- the sensory (afferent) receives the information from the environment
3- information processing in the central nervous system
4- the motor (efferent) receives an information fro the central nervous system to coordinate an action on effector organs

Question 8

Types of Sensory (2) and motor (2)

Answer 8

• Somatic Sensory: touch, pressure, vibration
• Visceral Sensory (autonomic): pain, nausea, hunger
• Somatic Motor: muscle contraction, joint movement
• Visceral Motor (autonomic): gland secretion, cardiac muscle contraction

Question 9

What’s the trajectory of an information in the cell of the nervous system?

Answer 9

1- The dendrite receives the information from another dendrite
2- the information is transfered to the cell body of the neuron
3- the information is after transported by the axon (covered by myelin to increase the speed of electrical impulses) to relay the information in the form of electricity
4- the information is transfered to the synapse and will do the synapsing (passes information onto other nerves or effector organ chemically) with the dentrite of another neuron

Question 10

Pathway of sensory and motor information

Answer 10

1- joints, skin, skeletal muscle 
2- somatic sensory fibers
3- CNS
4- somatic motor fibers
5- skeletal muscle

Question 11

muscle fibers are stimulated to contract by the nervous system. This stimulation or innervation of muscle fibers occurs via….

Answer 11

motor neurons

Question 12

motor unit definition?

Answer 12

one motor neuron innervating multiple muscle fibers (synchronous contraction)
- targeting specific muscle fiber

Question 13

What will happen if it’s a big motor unit

Answer 13

it will contract more muscle fibers

Question 14

What will happen if it’s a smaller motor unit

Answer 14

it will innervate less muscle fibers

Question 15

What’s the white matter?

Answer 15

Around the grey matter and contains the myelinated axons

Question 16

What’s the grey matter?

Answer 16

In the middle of the spinal cord and contains bundles of cell bodies

Question 17

How can you identify the dorsal root

Answer 17

the dorsal root has a ganglion and not the ventral root

Question 18

Which information passes through the dorsal rami?

Answer 18

information from the :

• skin of the back
• intrinsic muscles of the back

Question 19

Which information passes through the ventral rami?

Answer 19

informatiom from :

- everything else in the body (not the skin of the back nor the intrinsic muscle of the back)

Question 20

Explain the pathway of sensory and motor information if the information given is a push on your back.

Answer 20

1- The information enters by the dorsal ramus
2- passes into the spinal nerve
3- into the posterior root
4- goes in the sensory side (posterior) of the spinal cord
5- synapse from the sensory side to the motor (anterior) side of the spinal cord
6- leaves the motor side of the spinal cord by the anterior root
7- passes into the spinal nerve
8- and leaves by the dorsal ramus to give a motor reponse to your back

Question 21

Explain the pathway of sensory and motor information if the information given is a tap on your shoulder.

Answer 21

1- The information enters by the ventral ramus
2- passes into the spinal nerve
3- into the posterior root
4- goes in the sensory side (posterior) of the spinal cord
5- synapse from the sensory side to the motor (anterior) side of the spinal cord
6- leaves the motor side of the spinal cord by the anterior root
7- passes into the spinal nerve
8- and leaves by the ventral ramus to give a motor reponse to your shoulder

Question 22

where does the spinal cord from the cervical spine exit?

Answer 22

they exit above of their corresponding vertebrae

Question 23

where does the spinal cord from the thoracic and lumbar spine exit? and why?

Answer 23

They exit under their corresponding vertebrae

this is because in the cervical spine there is 7 vertebrae and 8 spinal nerve so C7 exits above CVII, but C8 can’t exit above CVIII because it doesn’t exits. Because of that it will exit above TI so the other spinal nerve will exit under their corresponding vertebrae

Question 24

What’s the conus medullaris?

Answer 24

It’s the end of the spinal cord at L1/L2

Question 25

What’s the filum terminale?

Answer 25

The extension of the spinal cord and it anchors into the tip of the coccyx

Question 26

what’s the cauda equina?

Answer 26

The spinal nerves for the sacral, coccygeal and lumbar

Question 27

What’s the name of the cervical enlargement

Answer 27

brachial plexus

Question 28

What’s the name of the lumbar enlargement

Answer 28

lumbosacral plexus

Question 29

Dura mater definition?

Answer 29

outher layer (protective) of the spinal cord 
part of the meninges

Question 30

Arachnoid mater definition?

Answer 30

middle layer of the spinal cord (looks like a spider web)

part of the meninges

Question 31

Pia mater definition?

Answer 31

inner layer of the spinal cord

part of the meninges

Question 32

denticulate ligaments definition?

Answer 32

connect the pia mater to the dura mater, prevents it from moving around

Question 33

where is the extradural/epidural space (and function)?

Answer 33

outside the dura mater filled with fat

function: to protect the dura mater

Question 34

where is the subdural space?

Answer 34

between the dura and arachnoid mater

Question 35

where is the subarachnoid space?

Answer 35

between the arachnoid and pia mater