Which of the following is not a function of astrocytes?
A) support and brace neurons
B) anchor neurons to blood vessels
C) guide the migration of young neurons, synapse formation, and helping to determine capillary permeability
D) control the chemical env
E) provide the defense for the CNS
Which of the choices below describes the ANS?
A) motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands
B) motor fibers that conduct nerve impulses from the CNS to skeletal muscles
C) sensory neurons that convey
A) motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands
What are ciliated CNS neuroglia that play an active role in moving the cerebrospinal fluid called?
A) ependymal cells
B) Schwann cells
C) oligodendrocytes
D) astrocytes
A) ependymal cells
The sheath of Schwann is also called the ________.
A) myelin sheath
B) axolemma
C) neurilemma
D) white matter
C) neurilemma
Bipolar neurons are commonly ________.
A) motor neurons
B) called neuroglial cells
C) found in ganglia
D) found in the retina of the eye
D) found in the retina of the eye
Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?
A) cholinesterase
B) norepinephrine
C) acetylcholine
D) gamma aminobutyric acid
C) acetylcholine
Which of the following describes the nervous system integrative function?
A) senses changes in the environment
B) analyzes sensory information, stores information, makes decisions
C) responds to stimuli by gland secretion or muscle contraction
B) analyzes sensory information, stores information, makes decisions
The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________.
A) resting period
B) repolarization
C) depolarization
D) absolute refractory period
D) absolute refractory period
Which of the following is not a special characteristic of neurons?
A) They conduct impulses.
B) They have extreme longevity.
C) They are mitotic.
D) They have an exceptionally high metabolic rate.
C) They are mitotic.
The part of a neuron that conducts impulses away from its cell body is called a(n) ________.
A) axon
B) dendrite
C) neurolemma
D) Schwann cell
A) axon
Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials?
A) mechanically gated channel
B) voltage-gated channel
C) leakage channel
D) ligand-gated channel
B) voltage-gated channel
An impulse from one nerve cell is communicated to another nerve cell via the ________.
A) cell body
B) synapse
C) receptor
D) effector
B) synapse
What is the role of acetylcholinesterase?
A) act as a transmitting agent
B) amplify or enhance the effect of ACh
C) destroy ACh a brief period after its release by the axon endings
D) stimulate the production of serotonin
C) destroy ACh a brief period after its release by the axon endings
Which of the following is not a function of the autonomic nervous system?
A) innervation of smooth muscle of the digestive tract
B) innervation of cardiac muscle
C) innervation of glands
D) innervation of skeletal muscle
D) innervation of skeletal muscle
Collections of nerve cell bodies outside the central nervous system are called ________.
A) nuclei
B) nerves
C) ganglia
D) tracts
C) ganglia
The term central nervous system refers to the ________.
A) autonomic nervous system
B) brain, spinal cord, and peripheral nerves
C) brain and spinal cord
D) spinal cord and spinal nerves
C) brain and spinal cord
The substance released at axon terminals to propagate a nervous impulse is called a(n) ________.
A) ion
B) cholinesterase
C) neurotransmitter
D) biogenic amine
C) neurotransmitter
A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.
A) efferent neuron
B) afferent neuron
C) association neuron
D) glial cell
C) association neuron
Saltatory conduction is made possible by ________.
A) the myelin sheath
B) large nerve fibers
C) diphasic impulses
D) erratic transmission of nerve impulses
A) the myelin sheath
Which of the following is not a chemical class of neurotransmitters?
A) acetycholine
B) amino acid
C) biogenic amine
D) ATP and other purines
E) nucleic acid
E) nucleic acid
Which of the following is false or incorrect?
A) An excitatory postsynaptic potential occurs if the excitatory effect is greater than the inhibitory effect but less than threshold.
B) A nerve impulse occurs if the excitatory and inhibitory effects are equ
B) A nerve impulse occurs if the excitatory and inhibitory effects are equal.
Select the correct statement regarding synapses.
A) Cells with interconnected cytoplasm are chemically coupled.
B) The release of neurotransmitter molecules gives cells the property of being electrically coupled.
C) Neurotransmitter receptors are located
D) The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another.
Ependymal cells ________.
A) are a type of neuron
B) are a type of macrophage
C) are the most numerous of the neuroglia
D) help to circulate the cerebrospinal fluid
D) help to circulate the cerebrospinal fluid
Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters are ________.
A) astrocytes
B) oligodendrocytes
C) microglia
D) Schwann cells
A) astrocytes
Schwann cells are functionally similar to ________.
A) ependymal cells
B) microglia
C) oligodendrocytes
D) astrocytes
C) oligodendrocytes
Immediately after an action potential has peaked, which cellular gates open?
A) sodium
B) chloride
C) calcium
D) potassium
D) potassium
Nerve cell adhesion molecules (N-CAMs) ________.
A) release nerve growth factor
B) are found on "pathfinder" neurons
C) are crucial in the production of neurotransmitters
D) are crucial for the development of neural connections
D) are crucial for the development of neural connections
An inhibitory postsynaptic potential (IPSP) is associated with ________.
A) a change in sodium ion permeability
B) hyperpolarization
C) opening of voltage-regulated channels
D) lowering the threshold for an action potential to occur
B) hyperpolarization
Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?
A) Specific sodium gates will open.
B) Specific potassium gates will open.
C) Sodium gates will open first, then close as pota
D) A single type of channel will open, permitting simultaneous flow of sodium and potassium.
When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________.
A) postsynaptic potential
B) excitatory potential
C) action potential
D) generator potential
D) generator potential
Which of the following is not true of graded potentials?
A) They are short-lived.
B) They can form on receptor endings.
C) They increase amplitude as they move away from the stimulus point.
D) They can be called postsynaptic potentials.
C) They increase amplitude as they move away from the stimulus point.
Which of the following is true about the movement of ions across excitable living membranes?
A) Ions always move actively across membranes through leakage channels.
B) Some ions are prevented from moving down their concentration gradients by ATP-driven pu
B) Some ions are prevented from moving down their concentration gradients by ATP-driven pumps.
A second nerve impulse cannot be generated until ________.
A) the membrane potential has been reestablished
B) the Na ions have been pumped back into the cell
C) proteins have been resynthesized
D) all sodium gates are closed
A) the membrane potential has been reestablished
In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is ________.
A) positively charged and contains less sodium
B) negatively charged and contains less sodium
C) n
B) negatively charged and contains less sodium
If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon ________.
A) the impulse would move to the axon terminal only
B) muscle contraction would occur
C) the impulse would spread bidirectionally
D)
C) the impulse would spread bidirectionally
Neurons may be classified according to several characteristics. Which of the following is correct?
A) Group A fibers are mostly somatic sensory and motor and are the smallest in diameter.
B) Group B fibers are highly myelinated and have the highest conduc
C) Group C fibers are not capable of saltatory conduction.
Select the correct statement about serial processing.
A) Spinal reflexes are an example of serial processing.
B) Input travels along several different pathways.
C) Smells are processed by serial pathways.
D) Memories are triggered by serial processing.
A) Spinal reflexes are an example of serial processing.