Overview of the CNS

Question 1

What is present in the neural tube early in development?

Answer 1

3 visible swellings or vesicles

Question 2

How are the 5 swellings present later in development created?

Answer 2

The first and third vesicles each subdivide

Question 3

What are the three primary vesicles?

Answer 3

Prosencephalon, mesencephalon, rhombencephalon

Question 4

What are the five secondary vesicles?

Answer 4

Telencephalon = gives cerebral hemispheres
Diencephalon = gives thalamus and hypothalamus Mesencephalon = gives midbrain 
Metencephalon = gives pons and cerebellum
Myelencephalon = gives medulla oblongata

Question 5

What secondary vesicles come from the division of the prosencephalon?

Answer 5

Telencephalon and diencephalon

Question 6

What secondary vesicles come from the division of the rhombencephalon?

Answer 6

Metencephalon and myelencephalon

Question 7

What structures comprise the brainstem?

Answer 7

Midbrain, pons and medulla oblongata

Question 8

What is the role of neurons?

Answer 8

Communicators = receive info chiefly via synapses, integrate info then transmit electrical impulses to another neuron/effector cell

Question 9

What is the structure of most neurons?

Answer 9

Multipolar with many dendrites and one axon

Question 10

Are glial cells or neurons more common in the CNS?

Answer 10

Glial cells are more numerous

Question 11

What are the types of glial cells found in the CNS?

Answer 11

Astrocytes, oligodendrocytes, microglia and ependymal cells

Question 12

What are some features of astrocytes?

Answer 12

Many numerous processes
Often star shaped
Roles in support, maintaining the BBB and environmental homeostasis

Question 13

What is the function of oligodendrocytes?

Answer 13

Produce myelin in the CNS

Question 14

What is the appearance of oligodendrocytes?

Answer 14

Numerous branches that extend to produce internodes of myelin around different axons
Round nucleus that stains moderately

Question 15

What are microglia?

Answer 15

Cells of similar lineage to macrophages = carry out immune monitoring and antigen presentation

Question 16

What is the appearance of microglia in the resting state?

Answer 16

Elongated nucleus and a number of short spiny cell processes

Question 17

What is the appearance of microglia in the active state?

Answer 17

Become rounder and take on an appearance similar to a macrophage

Question 18

What are ependymal cells?

Answer 18

Ciliated cuboidal or columnar epithelium that line the ventricles

Question 19

How can you differentiate fissures from sulci?

Answer 19

Fissures are deeper

Question 20

What is white matter?

Answer 20

Medullary centre = axons and their cell processes

Question 21

What is contained within grey matter?

Answer 21

Huge number of neurons, cell processes, synapses and support cells

Question 22

What are the lobes of the cerebral hemispheres?

Answer 22

Frontal, parietal, occipital, temporal and insular

Question 23

What are the relations of the frontal lobe?

Answer 23

Anterior to central sulcus and superior to the lateral sulcus

Question 24

What are the relations of the parietal lobe?

Answer 24

Posterior to the central sulcus
Superior to the lateral sulcus
Anterior to a line from the parieto-occipital sulcus to the pre-occipital notch

Question 25

What are the relations of the occipital lobe?

Answer 25

Posterior to line from the parieto-occipital sulcus to the pre-occipital notch

Question 26

What are the relations of the temporal lobe?

Answer 26

Inferior to the lateral sulcus | Posterior to line from the parieto-occipital sulcus to the pre-occipital notch

Question 27

Where does the temporal lobe extend medially?

Answer 27

From temporal pole to a line between the pre-occipital notch and the anterior end of the calcarine sulcus

Question 28

What are some features of the insular lobe?

Answer 28

Normally hidden | Plays important role in patient's experience of pain

Question 29

What are the meninges, from superficial to deep?

Answer 29

Dura mater, arachnoid mater and pia mater

Question 30

Where is the enteric nervous system found?

Answer 30

In the digestive system from the oesophagus to the rectum

Question 31

How are the neurons arranged in the enteric nervous system?

Answer 31

Into two plexuses in the wall of the gut

Question 32

What are the two plexuses of the enteric nervous system?

Answer 32

Myenteric plexus = located between outer layers of smooth muscle Submucosal plexus = located in submucosa

Question 33

What artery gives the majority of the blood supply to the brain?

Answer 33

Internal carotid artery

Question 34

How does blood drain from the brain?

Answer 34

Drains via system of dural venous sinuses

Question 35

Where do the dural venous sinuses drain into?

Answer 35

The internal jugular vein via the jugular foramen

Question 36

What is located in the calcarine sulcus?

Answer 36

Primary visual cortex

Question 37

What is the corpus callosum?

Answer 37

White matter structure connecting the left and right cerebral hemispheres