Chapter 15 [15.2c Cerebrospinal Fluid]
arachnoid granulations
#3
process of CSF production, circulation, removal
1. CSF is produced by the choroid plexus in the ventricles. 2. CSF flows from the third ventricle thru the cerebral aqueduct into the 4th ventricle. 3. CSF in the 4th ventricle flows into the subarchnoid space by passing thr the paired lateral apertunes of the single median aperture, and into the central canal of the spinal cord. 4. as the csf flows thru the subarachoid space, it removes waste products n provides buoyancy to supp the brain 5. excess csf flows into the arachnoid villi, then drains into the dura venous sinuses. the greater pressure on the CSF in the subarachnoid space ensures that CSF moves into the venous sinuses w/o permitting venous blood to enter the subarachnoid space.
protection
CSF provides a liquid cushion to protect delicate neural structures from sudden movements. - slows movements of brain
envmtal stability
CSF transports nutrients n chemicals to the brain n removes waste products from the brain. protects nervous tissue from chemical fluctuations that would disrupt neuron function.
CSF circulation 500 ml
choroid plexus produces CSF @ a rate of about ____ per day the csf circulates thru n eventually leaves the ventricles n enters the subarachnoid space
CSF
clear colorless liquid that circulates in the ventricles n subarachnoid space. bathes the exposed surfaces of the CNS n completely surrounds the brain n spinal cord.
arachnoid granulations
collections of arachnoid villi form
subarachnoid
excess CSF is continuously removed from the ____ space so the fluid wont accumulate n compress n damage nervous tissue.
csf circulation
excess CSF moves across the arachnoid mater membrane @ the arachnoid vili to return to the blood w/in the dural venous sinuses
arachnoid villi
fingerlike extensions of the arachnoid mater project thru the dura mater into the dural venous snuses to form ____
arachnoid villi
formed from fingerlike extensions of the arachnoid mater that project thru the dura mater into the dural venous sinuses
- buoyancy - protection - envmtal stability
functions of the CNS
formed by the choroid plexus in ea ventricle. which is composed of a layer of ependymal cells n the capillaries that lie w/in the pia mater.
how is CSF formed?
produced by secretion of a fluid from the ependymal cells that originates from the blood plasma.
how is csf formed?
choroid plexus
the ___ helps produce CSF, composed of ependymal cells n capillaries w/in the pia mater.
buyoancy
the brain floats in the CSF, which supp > 95% of its weight n prevents it from being crushed under its own weight. w/o CSf to supp it , the heavy brain would sink thru the foramen magnum!!!
