13 terms

Nervous System -- Meninges and CSF

dura mater
outermost meninx covering the brain; composed of tough fibrous connective tissue; outer layer forms periosteum of skull
pia mater
innermost meninx covering of the brain; delicate and highly vascular
arachnoid villi
structures instrumental in returning cerebrospinal fluid to venous blood in dural sinuses
arachnoid mater
middle meninx; cobweb-like in structure; secures arachnoid to pia mater
falx cerebri
dual fold that attaches the cerebrum to crista galli of skull; in longitudinal fissure
tentorium cerebelli
dural fold separating cerebrum from cerebellum; over cerebellum and in trasverse fissure
periosteal layer
superficial layer of dura mater attached to inner surface of skull
meningeal layer
deeper layer of dura mater forms true external covering of brain
falx cerebelli
dural fold along vermis of cerebellum
subarachnoid space
between arachnoid mater and pia mater; contains CSF and blood vessels
cerebrospinal fluid
found in and around brain and spinal cord; reduces brain weight by 97%; prevents brain from crushing under its own weight
choroid plexuses
produces CSF at constant rate; clusters of capillaries enclosed by pia mater and a layer of ependumal cells
blood-brain barrier
maintains stable environment for brain; separates neurons from some bloodborne substances