Chapter 13 checkpoint questions

a disease that damages myelin sheaths would affect the columns in the white matter of the spinal cord, due to the columns being composed of bundles of myelinated axons

A disease that damages myelin sheath would affect which portion of the spinal cord?

compression of the sciatic nerve produces the feeling of your leg falling asleep

Compression of which nerve produces the sensation that your leg has fallen asleep?

divergence, convergence, parallel processing serial processing, and reverberation

List the five circuit patterns found in neuronal pools

the CNS is made up of the brain and spinal cord, the PNS is made up of cranial and spinal nerves

Name the components of the CNS and PNS

innate reflexes

One of the first somatic reflexes to develop is the suckling reflex. Which type of reflex is this?

the infected neurons would be in the anterior gray horns of the spinal cord, where the cell bodies of somatic motor neurons are located

A person with polio has lost the use of his leg muscles. In which area of the spinal cord would you expect the virus-infected motor neurons to be?

this is a tendon reflex

A weight lifter is straining to lift 200-kg barbell above his head. Shortly after the lifts it to chest height, his muscles appears to relay and he drops the barbell. What reflex has occurred?

it indicates possible damage to descending tracts in the spinal cord

After injuring her back Tina exhibits a positive Babinski reflection. What does this imply about Tina's injury?

would affect the skin and muscles of the back of the neck and of the shoulders

An anesthetic blocks the function of the dorsal rami if the cervical spinal nerves. Which area of the body will be affected?

ventral root

Damage to which root of a spinal nerve would interfere with motor function?

a neuronal pool is a functional group of organized interneurons within the CNS

Define neuronal pools

a reflex is a rapid, automatic response to a specific stimulus

Define reflex

reinforcement is an enhancement of spinal reflexes, occurs when the postsynaptic neurons enters a state of generalized facilitation causeway chronically active excitatory synapses

Define reinforcement

a spinal reflex is a rapid, automatic response triggered by specific stimuli that is controlled in the spinal cord

Define spinal reflex

sensory nuclei receive and relay sensory info from peripheral receptors, motor nuclei issue motor commands to peripheral effectors

Differentiate between sensory nuclei and motor nuclei

during a withdrawal reflex, the limb of the opposite side is extended called a cross extensor reflex

During a withdrawal reflex of the foot, what happens to the limb on the side opposite the stimulus? What is this response called?

when intrfusal fibers are stimulated by gamma motor neurons, the muscle spindles become more sensitive. As a result little if any stretching stimulus would be needed to stimulate the contraction of the quadricep muscles in the patellar reflex

For the patellar reflex, how would the stimulation f the muscle spindle by gamma motor neurons affect the speed of the reflex?

all polysynaptic reflexes involve pools of interneurons; are intersegmental in distribution, and involve reciprocal inhibition, reverberating circuits, and the cooperation of several reflexes

Identify the basic characteristics of polysynaptic reflexes

cervical, brachial, lumbar, and sacral

Identify the major networks of nerves known as plexuses

dura mater, arachnoid mater, and pia mater

Identify the three spinal meninges

damage to the cervical plexus, more specifically the left and right phrenic nerve

Injury to which of the nerve plexuses would interfere with the ability to breathe?

the minimum number of neurons in a reflex arc is two. One must be a sensory neuron that brings impulses to the CNS and the other must be a motor neuron that transmits a response to an effector

That is the minimum number of neurons in a reflex arc

located in the subarachnoid space, which lies beneath the epithelium of the arachnoid mater and superficial to the pia mater

Where is the CSF that surrounds the spinal cord located?