C12 25-28

Question 0

Names of the meninges?

Answer 0

Dura mater, arachnoid mater, pia mater

Question 1

What are the meninges and what do they do? 4

Answer 1

3 CT membranes that:

• cover and protect the CNS,
• protect blood vessels and enclose venous sinuses,
• contain CSF,
• form partitions in the skull.

Question 2

Dura mater

Answer 2

Most durable, outermost layer.

Dense irregular CT.

Extends inward in certain areas to limit movement of the brain within the cranium.

Question 3

What are the 2 layers of the dura mater?

Answer 3

Periosteal layer, meningeal layer

Question 4

Periosteal layer of dura mater

Answer 4

More superficial layer / forms the periosteum on cranial bones.

Question 5

Meningeal layer of dura mater

Answer 5

usually fused to the periosteal layer

Has dural sinuses!

two layers separate to form large, blood-filled spaces called dural venous sinuses (sinus = modified vein). Dural sinuses drain blood from the brain.

Question 6

Arachnoid

Answer 6

Middle meninx that forms a loose brain covering composed of a web of collagen and elastic fibers.

Question 7

Epidural space

Answer 7

Between dura mater/skull bones

contains arteries and veins that nourish the meninges and bones of the cranium.

may become (epidural hematoma) if blood accumulates in it.

Question 9

subdural space

Answer 9

space between the arachnoid and dura mater - becomes an actual space if blood or fluid accumulates there. (subdural hematoma)

Question 10

subarachnoid space

Answer 10

Between arachnoid and pia mater.

a space that contains CSF, cerebral arteries and veins.

Question 11

Pia mater

Answer 11

Innermost layer - areolar ct clinging to brain.

Question 12

Where is CSF found?

Answer 12

Within the ventricles and surrounding the brain and spinal cord.

Question 13

What does CSF do?

Answer 13

Gives buoyancy to CNS structures (decrease weight by 97%, prevents from crushing itself),

protects brain and spinal cord from impact damage,

delivery system for nutrients and chemical signals from one part of the brain to another.

Question 14

What produces and circulates CSF?

Answer 14

The choroid plexus

Composed ependymal cells and blood capillaries that lie within the pia mater.

Question 15

hydrocephalus

Answer 15

Excessive CSF

Question 16

Where is the BBB reduced or missing in the CNS?

Answer 16

Hypothalamus - hormones and homeostasis (regulates water balance, body temp). Must be able to sample the chemical comp. of the blood.

Pineal gland - because it secretes melatonin directly into the blood stream.

Choroid plexus - needs access to blood in order to create csf.

Question 17

What components make the BBB?

Answer 17

Endothelium of the capillary wall,

feet of astrocytes

Question 18

Layers of meninges, etc 9

Answer 18

Skull
Epidural space
Periosteal layer
Dural sinus
Meningeal layer
Subdural space
Arachnoid
Subarachnoid
Pia mater