The Central Nervous System

Question 1

what makes up the central nervous system

Answer 1

the brain and spinal cord. lies within the skull and vertebral canal

Question 2

what is the spinal cord covered by

Answer 2

three different meninges
- dura mater
- arachnoid membrane
- pia mater

Question 3

what are the different segments/ regions of the spinal cord

Answer 3

• cervical
• thoracic
• lumbar
• sacral
• coccygeal

Question 4

what does grey matter contain

Answer 4

neuron cell bodies and some axons

Question 5

what does white matter contain

Answer 5

nerve axons

Question 6

explain dorsal horn grey matter

Answer 6

found in the dorsal or posterior part of the spinal cord.
location of first order afferent neuron terminals
contains cell bodies of second order sensory neurons

Question 7

explain ventral horn grey matter

Answer 7

ventral or anterior part of the spinal cord
contains cell bodies of motor neurons
motor neuron axons leave the cord via the ventral nerve roots

Question 8

why is white matter grey

Answer 8

because it is stained for myelin and therefore appears dark.

Question 9

how is white matter organised

Answer 9

into various groups of axons that serve particular functions

Question 10

describue the regional differences in grey and white matter

Answer 10

cervical - more white than grey
thoracic - more white than grey
lumbar - more grey than white
sacral - more grey than white

Question 11

describe the organisation of white and grey matter in the brain

Answer 11

the grey matter is on the outside

Question 12

describe the organisation of white and grey matter on the spinal cord

Answer 12

the white matter surrounds the grey matter

Question 13

what are the different regions of the brain

Answer 13

forebrain, midbrain and hindbrain

Question 14

what is found within the forebrain

Answer 14

the cerebrum and diencephalon

Question 15

what is found within the hindbrain

Answer 15

the pons, medulla oblongata and cerebellum

Question 16

what does the midbrain control

Answer 16

visual and auditory reflexes
pain control

Question 17

what does the hind brain control

Answer 17

vital centres, regulating breathing, heart, blood vessels, etc
also controls balance and posture

Question 18

what is found in the forebrain diencephalon

Answer 18

thethalamus and the hypothalamus

Question 19

what is the thalamus responsible for

Answer 19

sensory processing

Question 20

what is the hypothalamus responsible for

Answer 20

homeostasis - thermoregulation
hormone production
associated with the pituitary gland
circadium rhythms
motivation
emotional responses and stress

Question 21

what is the cerebrum responsible for

Answer 21

sensory and motor functions
language
memory
perceptions
sensory-motor integration
emotions

Question 22

what form of matter is the cerebrum

Answer 22

grey

Question 23

what form of matter is the corpus callosum

Answer 23

white

Question 24

what are the different regions of the lateral surface of the brain

Answer 24

frontal lobe
parietal lobe
temperol lobe
occipital lobe

Question 25

what is the function of the meninges surrounding the spinal cord

Answer 25

protection of the spinal cord

Question 26

why is white matter white

Answer 26

fat content - comes from the myelination of the matter. myelin is responsible for the presence of white matter in the cns

Question 27

where are cell bodies found in the cns

Answer 27

at the core of the spinal cord in two areas - the ventral horn at the front, and the dorsal horn at the back.

Question 28

why does the outskirts of the spinal cord have white matter

Answer 28

due to axons bringing information up and down the spinal cord

Question 29

give a summary on the dorsal grey horn

Answer 29

this is the posterior part of the spinal cord and is the location of first order afferent neuron terminals. the stain is for myelin and is found on white matter, which is white matter looks darker.

Question 30

give a summary on ventral horn grey matter

Answer 30

anterior portion of the spinal cord where the cell bodies of the motor neurons leave via ventral nerve roots.

Question 31

explain why there are reginal differences in the proportion of white and grey mattter in the spinal cord

Answer 31

every time you bring information or take it out, a cell body is needed. these generate grey matter. every time information is gathered, it needs to travel all the way up the brain stem through the white matter

Question 32

in what section of the brain can strokes have an impact on cranial nerves

Answer 32

the base of the brain

Question 33

what is the most prominent neuron in the cerebral cortex

Answer 33

the pyramidal cells. they are efferent neurons that integrate sensory information and initiate motor responses

Question 34

describe the dura mater

Answer 34

tough and fibrous, forms the outermost covering of the spinal cord. contains dense collagen fibres.

Question 35

describe the arachnoid layer

Answer 35

this is the middle layer and is simple squamous epithelium

Question 36

describe the pia mater

Answer 36

meshwork of collagen and elastic fibres that band to underlying neural tissue

Question 37

what are nissl bodies

Answer 37

regions of RER clusters and free ribosomes in the cytoplasm surrounding the nucleus of neural cell bodies

Question 38

what is the perikalyon

Answer 38

the cytoplasm surrounding the nucleus of neural cell bodies

Question 39

what is the axolemma

Answer 39

the plasma membrane of the axon

Question 40

what are telodendria

Answer 40

the axon terminal branches

Question 41

where are axon terminals found

Answer 41

at the end of telodendria

Question 42

what do collaterals allow

Answer 42

single neurons to communicate with several other cells

Question 43

what are plexuses

Answer 43

interwoven networks of spinal nerves.

Question 44

what are the different structural classifications of neurons

Answer 44

anaxonic bipolar unipolar multipolar

Question 45

what is an anaxonix neuron

Answer 45

has more than 2 processes and the axons are not obvious

Question 46

what is a bipolar neuron

Answer 46

two processes separated by cell bodies

Question 47

what is a unipolar neuron

Answer 47

a single long process

Question 48

what is a multipolar neuron

Answer 48

a single axon with multiple dendrites

Question 49

how long is the spinal cord usually

Answer 49

45 cm

Question 50

where is the amount of grey matter in the spinal cord greater

Answer 50

in the regions dedicated to sensory and motor control

Question 51

what are the different plexuses of the spinal cord

Answer 51

cervical brachial lumbosacral sacral

Question 52

where does the cervical plexus run from

Answer 52

c1-c5

Question 53

where does the brachial plexus run from

Answer 53

c5-t1

Question 54

what does the cervical plexus innervate

Answer 54

the muscles of the neck and diaphragm

Question 55

what does the brachial plexus innervate

Answer 55

pectoral girdle and upper limbs

Question 56

what are the major nerves of the lumbosacral plexus

Answer 56

femoral, obturator, and saphenous nerve

Question 57

what are the major nerves of the sacral plexus

Answer 57

gluteal and sciatic nerves

Question 58

what are the major nerves of the cervical plexus

Answer 58

- the lesser occipital nerve - great auricular nerve - trasnverse cervical nerve - supraciavicular nerve - phrenic nerve

Question 59

which region of the spinal cord contains cell bodies of the motor neurons

Answer 59

ventral horn grey matter

Question 60

which region of the spinal cord is the location of first afferent neuron terminals

Answer 60

dorsal horn grey matter

Question 61

what is found in the dorsal grey matter

Answer 61

first order afferent neuron terminals cell bodies of second order sensory neurons

Question 62

what are second order neurons

Answer 62

neurons that receive synaptic input from efferent neurons and then provide this to the spinal cord - act as a bridge between the primary neuron and the spinal cord. does not directly receive or deliver stimulus from or to effectors

Question 63

what is the corpus callosum

Answer 63

large white matter tract that connects the two hemispheres of the brain and allows us to perceive depth and communicate

Question 64

what is the arachnoid trabeculae

Answer 64

the arachnoid trabeculae are the network of collagen and elastic fibres that extend between the arachnoid membrane and the pia mater

Question 65

Answer 65

anaxonic neuron

Question 66

Answer 66

bipolar neuron

Question 67

Answer 67

interneuron

Question 68

Answer 68

motor neuron

Question 69

Answer 69

multipolar neuron

Question 70

Answer 70

sensory neuron

Question 71

Answer 71

unipolar neuron