Which of the following is NOT one of the basic functions of the nervous system?
integration of sensory input
control the activity of muscles and glands
regulation of neurogenesis
monitor changes occurring both inside and outside the body
regulation of neurogenesis
Which of the following allows us to consciously control our skeletal muscles?
the somatic nervous system
What part of the nervous system performs information processing and integration?
central nervous system
Which of the following types of glial cells monitors the health of neurons, and can transform into a special type of macrophage to protect endangered neurons?
microglia
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 peripheral nervous system (PNS) neuroglia form the myelin sheaths around larger nerve fibers in the PNS?
Schwann cells
Which of the following is true of axons?
Axons use chemically gated ion channels to generate graded
potentials.
A neuron can have only one axon, but the axon may have
occasional branches along its length.
Smaller (thinner)
axons are more likely to bear myelin sheaths than larger (thicker)
axons.
Neurons can have multiple axons but only one dendrite.
A neuron can have only one axon, but the axon may have occasional branches along its length.
Which of the following are gaps found along a myelin sheath?
nodes of Ranvier
Which of the following is NOT true of association neurons?
Association neurons account for over 99% of the neurons in the body.
Association neurons are also known as interneurons.
Most association neurons are confined within the peripheral nervous system (PNS).
Most association neurons are multipolar
Most association neurons are confined within the peripheral nervous system (PNS).
(Most association neurons are confined within the CNS (not PNS).
Neurons are also called nerve cells.
True or False?
True
Unmyelinated fibers conduct impulses faster than myelinated fibers.
True or False
False
(Myelinated fibers (axons bearing a myelin sheath) conduct nerve impulses rapidly, whereas unmyelinated fibers conduct impulses more slowly. Note that myelin sheaths are associated only with axons; dendrites are always nonmyelinated.)
Which neuroglia are the most abundant and versatile of the glial cells?
astrocytes
Which part of the neuron is responsible for generating a nerve impulse?
axon
Which of the following types of neurons carry impulses away from the central nervous system (CNS)?
motor
Which of the following is NOT a difference between graded potentials and action potentials?
Spatial summation is used to increase the amplitude of a graded potential; temporal summation is used to increase the amplitude of an action potential.
Graded potentials can result from the opening of chemically gated channels; action potentials require the opening of voltage-gated channels.
Graded potentials occur along dendrites, whereas action potentials occur along axons.
Greater stimulus intensity results in larger graded potentials, but not larger action potentials.
Spatial summation is used to increase the amplitude of a graded potential; temporal summation is used to increase the amplitude of an action potential.
Which of the following is a factor that determines the rate of impulse propagation, or conduction velocity, along an axon?
degree of myelination of the axon
The sodium-potassium pump ejects two Na+ from the cell and then transports three K+ back into the cell in order to maintain the concentration gradients for sodium and potassium.
False
(3Na+ to 2K+)
The __________ is due to the difference in K+ and Na+ concentrations on either side of the plasma membrane, and the difference in permeability of the membrane to these ions.
resting membrane potential
What type of stimulus is required for an action potential to be generated?
a threshold level depolarization
Which membrane potential occurs because of the influx of Na+ through chemically gated channels in the receptive region of a neuron?
excitatory postsynaptic potential
Which of the following is NOT one of the chemical classes into which neurotransmitters fall?
chlorides
Which neurotransmitter(s) is/are the body's natural pain killer?
endorphins
Which of the following is NOT a type of circuit?
converging circuits
pre-discharge circuits
reverberating circuits
diverging circuits
pre-discharge circuits
Which of the following circuit types is involved in the control of rhythmic activities such as the sleep-wake cycle, breathing, and certain motor activities (such as arm swinging when walking)?
reverberating circuits
Which neuron circuit pattern is involved in the control of rhythmic activities such as breathing?
reverberating circuit