1- Topography Of The Nervous System

Question 1

At what level of the spinal cord is there control of upper and lower limbs?

Answer 1

Cervical and lumbosacral enlargements

Question 2

What is grey matter mostly composed of?

Answer 2

Cell bodies and dendrites

Question 3

Why does white matter appear ‘white’?

Answer 3

Fatty content from myelin

Question 4

What is white matter mostly composed of?

Answer 4

Axons and supporting cells

Question 5

What is ‘grey matter’ in the peripheral nervous system termed?

Answer 5

Ganglion

Question 6

Roughly how many segment is the spinal cord composed of?

Answer 6

31 segments

Question 7

If a sensory deficit in seen in a dermatomal pattern where is it likely that the lesion is?

Answer 7

The dorsal root or spinal nerve level

Question 8

What is a funiculus?

Answer 8

A block of white matter containing multiple pathways in both directions (ascending and descending)

Question 9

In which funiculi would you find the lateral corticospinal tract and spinothalmic tract?

Answer 9

The lateral funiculus

Question 10

In which funiculi would you find the dorsal column tract?

Answer 10

The dorsal funiculus

Question 11

In which funiculi would you find the ventral corticospinal tract?

Answer 11

The ventral funiculus

Question 12

What is a tract?

Answer 12

A white matter pathway connecting two distinct regions of grey matter

Question 13

What is a fasiculus?

Answer 13

A subdivision of a tract that supplies a distinct region of the body

Question 14

what are two examples of fasiculi that are subdivisions of the dorsal column tract and where do they supply?

Answer 14

Gracile fasiculus- lower half of body

Cuneate fasiculus- upper half excluding the head

Question 15

Is the dorsal column tract sensory or motor?

Answer 15

Sensory

Question 16

How are the cell bodies of the grey matter organised?

Answer 16

Into cell columns called Rexed laminae

Question 17

What is a nucleus?

Answer 17

A collection of functionally related cell bodies

Question 18

What is the cerebral cortex?

Answer 18

Outer layer of grey matter found on cerebral hemispheres and cerebellum

Question 19

What is a fibre in comparison to just an axon?

Answer 19

Fibre is an axon and its supporting cells

Question 20

What do association fibres connect?

Answer 20

Cortical regions within a hemisphere, e.g adjacent gyri

Question 21

What do commissural fibres connect? and give an example..

Answer 21

The left and right hemispheres

E.g corpus callosum

Question 22

What do projection fibres connect?

Answer 22

The cerebral hemispheres with the brain stem and the cord

Question 23

What are some roles of the periaqueductal grey matter surrounding the cerebral aqueduct?

Answer 23

Pain transmission and micturition

Question 24

The superior and inferior colliculi of the midbrain regulate reflex responses to what stimuli?

Answer 24

Superior- visual stimuli

Inferior- auditory stimuli

Question 25

What cranial nerve exits from the lateral aspect of the pons?

Answer 25

Trigeminal nerve

Question 26

What is the pons important for?

Answer 26

Feeding and sleep

Question 27

What part of the cerebellum herniates through the foramen magnum with increased intracranial pressure and why can this lead to death?

Answer 27

The cerebellar tonsils can herniates compressing the cardio and respiratory centres of the medulla

Question 28

What structure in the ventricles makes CSF?

Answer 28

Choroid plexus

Question 29

What are the functions of CSF? (metabolic and mechanical)

Answer 29

Shock absorbs the brain and renders it effectively weightless
Contains glucose for metabolism

Question 30

Where is CSF reabsorbed?

Answer 30

Arachnoid granulations extend into the superior sagittal sinus where CSF enters the venous blood

Question 31

Through where does the CSF drain from the lateral to the third ventricle?

Answer 31

Interventricular foramen

Question 32

Via what structure does CSF drain form the third ventricle to fourth ventricle?

Answer 32

Cerebral aqueduct