Midterm Review Flashcards
Which is true of a neuron with a resting potential?
Sodium pump has moved Na+ to the outside of the plasma membrane
The first even to occur when an adequate stimulus is applied to a neuron is what?
Some of the sodium channels at the point of stimulation open
What is true of an action potential?
The outside of the plasma membrane is negatively charged, and the inside is positively charged
The only ion that can diffuse across a neuron’s membrane when the neuron is at rest is what?
Potassium
A slight shift away from the resting membrane potentials in a specific region of the plasma membrane is called a _______ potential.
Local
During a relative refractory period, what happens?
The action potential can be intimated with a strong stimulus
A lack of which neurotransmitter is associated with Parkinson’s disease:
Dopamine
The efferent pathways of the autonomic system consist of which nervous systems?
Sympathetic and Parasympathetic
What does a synapse consist of?
Synaptic knob, synaptic cleft, and plasma membrane of postsynaptic neuron
Where is a synaptic knob located?
Axon
Which of the following is not a function of a central nervous system?
All of the above are functions of the CNS
Excitatory neurotransmitters are most likely to what?
Initiate an action potential
When current leaps across an insulating myelin sheath from node to node, the type of impulse conduction is called what?
Saltatory Conduction
Gray matter in the brain and spinal cord consists primarily of what?
Cell bodies
The myelin sheath is formed by what?
Schwann cells
Neurons in the CNS have less chance of regenerating all of the following reasons except what?
Microglia lay down scar tissue
Serotonin is an example of what?
Amine neurotransmitter
The layer of the meninges that serves as the inner periosteum of the cranial bone is the what?
Dura mater
The innermost layer of the meninges is the what?
Pia mater
What is true of the reflex arc?
It always consists of an afferent neuron and an efferent neuron
Multipolar neurons have what?
Multiple dendrites and one axon
Cerebrospinal fluid is found in all of the following except what?
Subdural space
How many ventricles are in the brain?
Four
Cerebrospinal fluid is formed by filtration of blood in what?
Choroid plexuses
Cerebrospinal fluid circulates through the ventricle, into the central canal and _______ is absorbed back into the blood.
Subarachnoid space
If the dorsal root ganglia of the spinal nerve were destroyed, a person would lose ______ related to that pathway.
Sensory Perception
If the ventral root of a spinal nerve were destroyed, a person would lose _____ related to that pathway.
Willed movement
Which of hte following is not true of the lateral corticospinal tract fibers?
Most inhibit the lower motor neuron
Impulses sent over which of the following tracts could result in voluntary movement, especially of the hands, fingers, feet, and toes of the opposite side
Lateral Corticospinal
The spinal tract that is located in the side of the cord, originates in the brain, and terminates in the spinal cord is the ___________ tract.
Lateral corticospinal tract
Nerve fibers of the spinothalamic tract are what?
Sensory
White matter of the nervous system is made up of what?
Myelinated fibers
The brain has how many major divisions?
Six
The brain stem does not include the what?
Cerebellum
All of the following cranial nerves have a functional classification of motor except what?
Vestibulocochlear
Tic douloureux is a painful neuralgia of the what nerve?
Trigeminal
The nerve commonly called the vagus nerve is the _____ cranial nerve.
X (10th)
Which of the following cranial nerves is responsible for movement of the tongue?
Hypoglossal
All of the following cranial nerves are involved in proprioception except the what?
Vagus
Which of the following is not plexus of the spinal nerves?
Thoracic
The cervical plexus is:
All of the above
Which plexus contains nerves that innervate the lower part of the shoulder and the entire arm?
Brachial
The sensory cranial nerves include only the what?
Olfactory, optic, and vestibulocochlear
The cranial nerve that arises from the spinal cord is the what?
Accessory
Nerve impulses over the ______ nerve cause increased peristalsis and decreases heart rate.
Vagus
The spinal nerves are connected to the spinal cord and consist of how many pairs?
31
Spinal nerves are mostly _____ fibers?
Motor and sensory
A mixed nerve is one that what?
Carries both sensory and motor fibers
Damage to the ____ nerve could make the diaphragm unable to function.
Phrenic
The phrenic nerve is found in which plexus?
Cervical
Which generalization concerning the autonomic nervous system is not true?
All of its axons are afferent fibers
Which of the following would not be a major effect for the autonomic nervous system?
Skeletal muscles
Somatic motor and autonomic pathways share all of the following characteristics except what?
Number of neurons between CNS and effector
The autonomic nervous system functions chiefly in the what?
Innervation of smooth muscle in the viscera
Once inside the sympathetic chain ganglion, the preganglionic fiber may:
- Synapse with the sympathetic postganglion neuron
- Send ascending and/or descending branches through the sympathetic trunk to synapse with postganglionic neurons in other chain ganglia
- Pass through one or more ganglia without synapsing
- All
All
Sympathetic responses generally have widespread effects on the body because why?
Preganglionic fibers synapse with several postsynaptic fibers
Parasympathetic neuron cell bodies are located where?
Nuclei of the brainstem and the lateral grap columns of the sacral cord
Which of the following is not an example of sympathetic stimulation?
Constriction of the bronchioles
All of the following are examples of parasympathetic stimulation except what?
Increased heart rate