Lecture 11

Question 1

What are the three meninges and what do they do?

Answer 1

Protect neural tissue
dura mater
arachnoid membrane
pia mater

Question 2

How many ventricles are there and what is their function?

Answer 2

4, to hold and produce cerebrospinal fluid by the choroid plexus

Question 3

What is the function of the CSF?

Answer 3

1) protect brain through buoyancy, shock absorption
2) regulate exchange and deliver nutrients/remove waste from the brain –> from the arachnoid villi
balance between too much pressure and not enough protection

Question 4

How is the blood-brain barrier different than typical exchange membranes?

Answer 4

much tighter due to the presence of tight junctions

this is promoted by the foot processes of astrocytes releasing paracrine signals

Question 5

Describe the cross-section of the spinal cord

Answer 5

Has grey (unmyelinated collection of cell bodies) matter and white (myelinated axons) matter. The white matter is split into ascending and descending tracts. the grey matter is split into ventral and dorsal. The dorsal root carries afferent info to the CNS, while the ventral root carries efferent signals to the muscles and glands. the dorsal horn contains the afferent visceral and somatic nuclei and the ventral horn contains the somatic and autonomic efferent nuclei.