Central Nerous System quiz 2

spinal cord

extends from foramen magnum to 2nd lumbar (L2); protected by vertebral column; nerves allow movement; damage could cause paralysis

gray matter

center of spinal cord; looks like butterfly or letter H; no myelinated axons

white matter

outside of spinal cord; contains myelinated fibers; 3 columns - dorsal, ventral, lateral

ascending tracts

axons that conduct action potentials TOWARD brain; sensory pathways (temp, touch, pain); white matter

descending tracts

axons that conduct action potentials AWAY from brain; controls different types of movements; white matter

Posterior horns

contain axons which synapse with interneurons; gray matter

Anterior horns

contain somatic neurons; gray matter

lateral horns

contain autonomic neurons; gray matter

central canal

fluid filled space in center of food; gray matter

spinal nerves

31 pairs; 3 major plexuses; sensory and somatic neurons; along spinal cord from dorsal to ventral

plexuses

network of nerves

Cervical plexus

spinal nerves C1-4; supplies nerves to muscles attached to hyoid bone and neck; contains phrenic

Brachial Plexus

spinal nerves C5-T1; supply nerves to upper limb, shoulder, hand

lumbosacral plexus

spinal nerves L1-S4; supply nerves to lower limbs

cerebrospinal fluid

bathes brain and spinal cord; protective cushion around CNS; produced in choroid plexus of brain

Meninges

protective wrapping around brain and spinal cord

meningitis

bacterial or viral infection of meninges

Dura mater

type of meninges; "tough mother"; outermost layer; thickest layer of connective tissue

Dural venous sinuses

space within 2 layers of dural matter; collects blood

Epidural space

in vertebral canal sinus separates dura mater from vertebrae; injection site for epidural anesthesia during childbirth

arachnoid mater

2nd layer of meninges; think spider web-like tissue

Subarachnoid space

where cerebrospinal fluid sits

spinal block

anesthetic injected to numb spinal nerves

spinal tap

cerebrospinal fluid can be removed for examination of diseases

pia mater

3rd layer of meninges; tightly bound to surface of brain and spinal cord