Card Set Information
Spinal Cord, spinal nerves, and spinal reflexes
Name the components of the central nervous system and the peripheral nervous system
: Brain and spinal Cord
: cranial nerves and spinal nerves
Define spinal reflex
A rapid, automatic response triggered by specific stimuli
Identify the three spinal meninges.
Dura mater, arachnoid mater, pia mater
Damage to which root of a spinal nerve would interfere with motor function
-Ventral root of a spinal nerve, which is composed of both visceral an dsomatic motor fibers
Where is the cerebrospinal fluid that surrounds the spinal cord located
Subarachnoid space, which lies beneath the epithelium of the arachnoid matter and superfucial to the pia mater
Differentiate between sensory nuclei and motor nuclei
Sensory nuclei receive and relay sensory info from peripheral receptors. Motor nuclei issue motor commands to peripheral effectors
A person with polio has lost the use of his leg muscles. In which area of his spinal cord would you expect the virus-infected motor neurons to be
in the anteriour gray horns of the spinal cord, where the cell bodies of somatic motor neurons are located
A disease that damages myelin sheaths would affect which portion of the spinal cord?
columns, because they are composed of bundles of myelinated axons
Identify the major networks of nerves known as plexuses
cervical, brachial, lumbar, sacral and coccygeal
An anesthetic blocks the function of the dorsal rami of the cervical spinal nerves. Which areas of the body will be affected?
skin and muscles of the back of the neck and the shoulders
Injury to which of the nerve plexuses would interfere with the ability to breathe.
Cervical plexus -more specificallly phrenic nerves- which originate in this plexus and innervate the diaphragm
Compression of which nerve produces the sensation that your leg has "fallen asleep"
the functional group of interconnected neurons organized within the CNS
List the five circuit patterns found in neuronal pools
divergence, convergence, serial processing, parallel processing, and reverberation
a rapid, automatic response to a specific stimulus. Important in homeostasis
What is the minimum number of neurons in a reflex arc?
two. One must be a sensory that brings and the other a motor neuron that transmits to the effector
One of the first somatic reflexes to develop is the suckling reflex. What type of reflex is this?
Identify the basic characteristics of polysynaptic reflexes
All involve pools of interneurons
Are intersegmental in distribution
involve reciprocal inhibition
For the patellar (knee jerk) reflex, how would the stimulation of the muscle spindle by gamma motor neurons affect the speed of the reflex
The muscle spindles become more sensitive,
reflex would appear more quickly
A weight lifter is straining to lift a 200-kg barbell above his head. Shortly after he lifts it to chest height, his muscles appear to relax and he drops the barbell. Which reflex has occurred.
During a withdrawal reflex of the foot, what happens to the limb on the side opposite the stimulus? What is this response called?
The limb on the opposite side is extended, called cross extensor reflex