Block 4 - The central nervous system (CNS)

Question 1

What are meninges?

Answer 1

Dura matter, arachnoid matter, Pia matter.

Arachnoid barrier cells (ABC) form junctions separating subarachnoid space from surrounding space

Question 2

What is cerebrospinal fluid?

Answer 2

Found in the arachnoid space

Ion composition similar to blood plasma - but higher chloride conc and Iower protein conc.

Question 3

How is blood supplied to the brain?

Answer 3

Blood vessels cross the meninges to supply brain with oxygen nutrients. Removes carbon dioxide and waste.

Question 4

What is an ischaemic stroke caused by?

Answer 4

A blocked blood vessel

Question 5

What is a hemorrhagic stroke caused by?

Answer 5

A ruptured aneurysm

Question 6

What is the blood-brain barrier and it’s role in the CNS?

Answer 6

Endothelial cells (walls of blood vessels)

Role:
Protects the CNS from toxins and pathogens - can also hinder treatments

Question 7

What structures are in the lower level of the CNS?
What is it’s role?

Answer 7

Spiral chord + brainstem
Reflexes and local circuits