Chapter 13 The Spinal Cord, Spinal Nerves, and Somatic Reflexes
Correctly indicate how many of each of spinal nerve emerges from the spinal cord.
Thoracic : 12 pairs Lumbar : 5 pairs Cervical : 8 pairs
A nerve is:
composed of numerous nerve fibers (fascicles) bound together by connective tissue
A ____ is a cluster of neuron cell bodies outside of the CNS.
ganglion
Post-ganglionic ____ nerve fibers innervate skin, skeletal muscles, bones, and joints.
somatic
Place in order the components of a reflex arc pathway.
1. receptor 2. afferent nerve fiber 3. integrating center 4. efferent nerve fiber 5. effector
perineurium
connective tissue that surrounds bundles
There are how many pairs of spinal nerves?
31
Which spinal cord areas are composed of gray matter?
Anterior horn Lateral horn Posterior horn
Name the typical location for muscle spindles.
At the ends of a muscle, near the tendons
Which of the following are extensions of the pia mater that anchor the spinal cord?
Denticulate ligaments
Somatic fiber
Nerve fiber that innervates skin, skeletal muscles, bones and joints
What are the three columns of white matter found in the spinal cord?
Posterior Anterior Lateral
Which of the following are functions of the spinal cord?
Reflexes Locomotion Conduction
What is subarachnoid space?
The space between the arachnoid mater and pia mater
What is the subarachnoid space?
The space between the arachnoid mater and pia mater
____ matter is composed of myelinated and unmyelinated axons and is superficial to the gray matter of the spinal cord.
White
Guillain-Barre syndrome
acute demyelinating nerve disorder
Which of the following is/are considered a distal branch of spinal nerve?
anterior ramus posterior ramus
Indicate which of the following is the name of a plexus.
cervical sacral lumbar
Because the nerve tracts of the spinal cord undergo ___, the right side of the brain communicates with the left side of the body, and vice versa.
decussation
What is the dural sheath around the spinal cord made of?
dura mater
A nerve containing both sensory and motor nerve fibers is called a ____ nerve.
mixed
Moving peripherally from the spinal cord, the anterior and posterior ___ form the spinal nerve.
roots
The four components of a monosynaptic somatic reflex arc.
afferent nerve fiber receptor in skin, muscle or tendon efferent nerve fiber skeletal muscle
The ___ matter that consists of simple squamous epithelium with a mesh of fibers in the adjoining space.
arachnoid
The neural pathway that mediates a reflex is called a reflex ___, consisting of a receptor, afferent nerve fiber, interneurons, efferent nerve fiber, and effector.
arc
Because it contains ascending and descending nerve tracts, a function of the spinal cord is the _____ of nerve signals between the CNS and the periphery of the body.
conduction
External to the neurilemma of a nerve fiber is the layer of loose connective tissue that surrounds a nerve fiber called the ...
endoneurium
The ____ is the layer of loose connective tissue surround an individual nerve fiber.
endoneurium
The dense irregular connective tissue layer enclosing an entire nerve is called the _____.
epineurium
Within a nerve, nerve fibers are gathered into bundles called ...
fascicles
A _____ is a tract of nerve fibers within column of the spinal cord.
fasciculus
The ___ matter of the central nervous system is where the neuron cell bodies, dendrites, and synapses are found.
gray
The ___ matter of the spinal cord contains the synapses and therefore is the site of synaptic integration.
gray
All spinal nerves except C1 pass through a(n) ____ foramen to emerge from the vertebral column.
intervertebral
Define efferent fiber
motor nerve fiber
A ____ is a cord like organ composed of numerous nerve fibers (fascicles) bound together by connective tissue.
nerve
The spinal nerve roots carrying sensory nerve signals are the ___ roots.
posterior
Examples of somatosensory stimuli:
pressure touch heat-cold nociception stretch
Where is white matter in the spinal cord?
superficial to the gray matter
It takes ___ neurons for a somatic sensation nerve signal to complete the sensory pathway.
three
In the CNS, bundles of axons that make up white matter are called ___.
tracts
