9-2 Central Nervous System Flashcards
The spinal cord is located within the?
vertebral canal
What protects the spinal cord?
- vertebral column
- vertebral ligaments
- meninges
- cerebrospinal fluid
What are the three layers of the meninges?
- dura mater
- arachnoid mater
- pia mater
Which layer of meninges:
- is the outer most layer
- tough dense connective tissue
dura mater
Which layer of meninges:
- middle layer
- resembles spider web
- extends into the subarachnoid space
arachnoid mater
Which layer of meninges:
- inner layer
- thin and delicate
- adheres to the surface of the spinal cord and brain
- contains blood vessels
pia mater
Subarachnoid space is between the arachnoid and pia mater and is filled with?
cerebrospinal fluid
Describe the location of the epidural space?
between vertebrae and dura mater
The spinal cord extends from the ______ to the?
- medulla oblongata
- 2nd lumbar vertebrae
What are the two grooves that divide the spinal cord into two hemispheres?
- anterior median fissure
- posterior median sulcus
Where is the central canal located?
What is it filled with?
- in the center of the gray matter
- cerebrospinal fluid
The spinal cord has how many pairs of spinal nerves?
31
What are two bundles of axons that connect each spinal nerve to a segment of the cord?
roots
What contains sensory axons which conduct nerve impulses from sensory receptors (afferent)?
posterior root
What contains axons of motor neurons (autonomic and somatic)
which conduct nerve impulses from the CNS to the effectors (efferent)?
anterior root
Has tracts that serve as highways for nerve impulses
white matter
What receives and integrates incoming and outgoing
information and is a site for integration of reflexes?
gray matter
What structure contains:
- neuronal cell bodies
- dendrites
- unmyelinated axons
- axon terminals
- neuroglia
gray matter
Gray matter is subdivided into left and right regions called?
horns
Each left and right region of the gray matter has how many horns?
-What are the names? (relative to their position)
- 3
- anterior, lateral, posterior
Which portion of the gray matter contains cell bodies and axons of neurons as well as axons of incoming sensory neurons?
posterior horn
Which portion of the gray matter contains cell bodies of somatic motor neurons that provide impulses for contraction of muscles?
anterior (ventral) gray horns
The lateral horn is only present in the?
thoracic and upper lumbar segments
What portion of the gray matter contains cell bodies of autonomic motor neurons that regulate the cardiac muscle, smooth muscle, and glands?
lateral gray horns
What has myelinated axons, gray or white matter?
white matter
What consists of axons that conduct nerve impulses toward the brain?
sensory (ascending) tract
What is an example of the sensory tract?
spinothalamic tract
What consists of axons that conduct nerve impulses away from the brain?
motor (descending) tract
What is an example of the motor tracts?
corticospinal tract
Fast, involuntary sequences of actions in response to stimuli
reflexes
Reflexes can be classified as?
- simple
- complex
What are the two levels of reflexes?
- spinal reflex
- cranial reflex
Which level of reflex is this:
- simple
- reflex arc
- example: patellar reflex
spinal reflex
Which level of reflex is this:
- simple
- occurs in the brainstem
- example: gag reflex
cranial reflex
Spinal nerve are part of which nervous system?
peripheral
Spinal nerves connect the ____ to the ______ receptors and muscles of the body
- CNS
- sensory
How many pairs of spinal nerves are there?
-31 pairs
How many pairs of spinal nerves are in the cervical region?
-Thoracic?
- 8
- 12
How many pairs of spinal nerves are in the lumbar region?
- sacral?
- coccyx?
- 5
- 5
- 1
Each spinal nerve is connected to the spinal cord by which roots?
- anterior (motor) root
- posterior (sensory) root
Sensory information goes through which root?
dorsal
Motor information goes through which root?
anterior