47 terms

Chapter 13: Meninges-spinal nerves

What is the membrane the CNS is surrounded by that lie between the bone and soft tissue?
dura mater, arachnoid mater, pia mater
Three layers of the meninges.
dura mater
Outermost layer of meninges
epidural space
What is the dura mater separated from the vertebrae by?
arachnoid mater
Middle layer of the meninges with a web-like structure
subarachnoid space
What is between the arachnoid and pia mater
cerebrospinal fluid
What does the subarachnoid space contain
pia mater
Innermost layer of the meninges
pia mater
What hugs the surface of meninges and follows its irregular contours
cerebrospinal fluid
Clear, colorless fluid
80-150 ml
Total volume of CSF
supports, nourishes, provides a pathway for wastes
Functions of cerebrospinal fluid
What are the four cavities of the brain called?
choroid plexus
Masses of blood capillaries in rain ventricles that produce CSF
ependymal cells
What covers capillaries and form a cerebrospinal fluid barrier
arachnoid vili
CSF is reabsorbed by what?
foramen magnum
Where does the spinal cord begin?
first and second lumbar vertebrae
Where does the spinal cord terminate between?
How many segments does the spinal cord consist of?
The spinal nerves connect what to what?
cervical enlargement
What is the thickening in the spinal cord in the neck region that supplies nerves to upper limbs
lumbar enlargement
Thickening of the spinal cord in the lower back that gives off nerves to lower limbs.
conus medullaris
Conical tapering of spinal equine
filum terminale
What arises at conus medullaris
cauda equine
The lumbar, sacral, and coccygeal nerves descent beyond the end of the cord forming a structure called what?
anterior median fissure and posterior medial sulcus
Two deep longitudinal grooves that divide the cord into right and left halves.
posterior horns and anterior horns
Gray matter is divided into right and left wings of gray matter called what?
lateral horn
Between posterior and anterior horns is a protrusion of gray matter called what?
motor fibers
Neurons with large cell bodies located in the anterior horns give rise to what that pass through spinal nerves to skeletal muscles
gray commissure
What is the horizonal bar of gray matter in the middle of the spinal cord which connects the right and left sides
central canal
What does the gray commissure surround that is filled with CSF
What is a majority of gray matter in the spinal cord
anterior, posterior, lateral
Three regions that gray matter divides while matter of the spinal cord into
nerve tracts
Each funiculus consists of longitudinal bundles of myelinated nerve fibers that comprise major nerve pathways called what?
sensory nerves
What enters posterior cord
cell bodies
Dorsal root of ganglia are masses of what?
Motor nerves
What exits the anterior cord
spinal nerves
What do anterior and posterior roots form?
transmit nerve impulses and house spinal reflexes
Two major functions of spinal cord?
nerve tracts
What part of the spinal cord provides communication between the brain and PNS
ascending tracts
Tracts that carry information to the brain
descending tracts
Tracts that conduct motor impulses away from the brain
What are the nerve fibers within the ascending and descending tracts?
cord-like bundle of nerve fibers held together by layers of connective tissue
sensory nerves
Nerves that conduct impulses into the brain and spinal cord
motor nerves
nerves that carry impulses to muscles or glands
mixed nerves
nerves that include both sensory and motor