Chapter 9
Which of the neuroglial cell types shown are found in the PNS?
E
The autonomic nervous system is under voluntary control; whereas, the somatic nervous system is involuntary.
False
Which of the following is NOT a type of circuit?
pre-discharge circuits
Which of the following types of glial cells produces the myelin sheaths that insulate axons, or nerve fibers, in the central nervous system (CNS)?
oligodendrocytes
Which of the following is the conducting region of the neuron?
axon
Which area would contain an abundance of vesicles containing neurotransmitter?
E
Which of the choices below describes the ANS?
motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands
Which of the following allows us to consciously control our skeletal muscles?
the somatic nervous system
During depolarization, the inside of the neuron's membrane becomes less negative.
True
The action potential is caused by permeability changes in the plasma membrane.
True
Neurons in the CNS are organized into functional groups.
True
The part of a neuron that conducts impulses away from its cell body is called a(n) ________.
axon
Which neuroglia are the most abundant and versatile of the glial cells?
astrocytes
What structural classification describes this neuron?
multipolar
The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________.
absolute refractory period
If bacteria invaded the CNS tissue, microglia would migrate to the area to engulf and destroy them.
True
What part of the nervous system performs information processing and integration?
central nervous system
Axon diameter and degree of myelination determine nerve impulse conduction velocity
True
Which of the following are gaps found along a myelin sheath?
nodes of Ranvier
Which areas of this neuron would be classified as receptive regions?
Both A and B
Schwann cells are functionally similar to ________.
oligodendrocytes
Neuroglia that control the chemical environment around neurons by buffering ions such as potassium and recapturing and recycling neurotransmitters are ________.
astrocytes
What does the central nervous system use to determine the strength of a stimulus?
frequency of action potentials
Which of the following peripheral nervous system (PNS) neuroglia form the myelin sheaths around larger nerve fibers in the PNS?
Schwann cells
The term central nervous system refers to the ________.
brain and spinal cord