ch 13

To contact a Schwann cell, where would a microprobe have to be inserted in the nervous system?

along any axon in the PNS, myelinated or not

If the CNS was susceptible to a drug that should not affect it, this might indicate damage to which of the following cells?

astrocytes

Cardiac muscle, smooth muscle, and glands are under the control of the

autonomic nervous system

The portion of a neuron that carries information in the form of a nerve impulse is called the

axon

The area that connects the cell body to the axon is called the

axon hillock

Movement of nutrients, wastes, and organelles between the cell body and axon terminals is called

axoplasmic transport

Pathways leading from the receptors to the CNS are called

both afferent and sensory pathways

Which of the following are examples of neuroeffector synapses?

both neuromuscular synapse and neuroglandular synapse

The anatomical subdivisions of the nervous system are (the)

central and peripheral nervous systems.

Nerve impulse transmission between cells of the CNS without any delay can be attributed to

communicating junctions that permit the passage of ions between the cells

When a neural pathway splits to involve many areas of the nervous system, the type of processing is known as

diverging

Muscles, glands, and special cells that respond to neural stimuli are called

effectors

Which of the following neuroglia produce cerebrospinal fluid?

ependymal cells

Demyelination

is the gradual reduction in myelin

Because a neuron loses its centrioles,

it is rendered incapable of dividing

The surface of the brain is called the

neural cortex

Which of the following is gray matter?

neural cortex

The outermost covering of a myelinated axon is called (the)

neurolemma

Cells responsible for information processing and transfer are

neurons

Areas of a myelinated axon that are not covered by myelin are called

nodes

Axons extending from a peripheral ganglion to an effector are called

postganglionic fibers

Generation of an action potential at an axon of a neuron may be caused by

stimulation of any portion of the dendrites of the nueron and/or input from presynaptic cells

Neurotransmitters are

stored in synaptic vesicles

Neuroglia in the nervous system function to

support the neurons

Involuntary cardiac muscle fibers on the heart are innervated by

visceral motor fibers

The CNS includes the

Brain and spinal cord.

If all of the glial cells of the nervous system were destroyed, which of the following would occur?

Less than 20 percent of the cells of the nervous system would remain

Over 50 different neurotransmitters have been identified, but the best known is

acetylcholine

The structural classification of a neuron is based upon

the number of processes that project from the cell body

Satellite cells surround the cell bodies of peripheral neurons, which can be found in (the)

ganglia

Organized masses of axons and neuron cell bodies in both the CNS and the PNS

have distinct anatomical boundaries

At a vesicular synapse the neurons communicate by

neurotransmitters

Areas of gray matter in the interior of the CNS form larger groups called

nuclei

Which type of cell can only be found in the central nervous system?

oligodendrocytes

The functional classifications of neurons includes ________, which carry information toward the CNS.

sensory neurons

Which of the following structures do not contribute to the coarse grainy appearance of the perikaryon of a neuron?

smooth endoplasmic reticulum

Injured nuerons can recover their functional capabilities if

the oxygen and nutrient supplies are restored

Areas of the nervous system that are dense in myelinated axons are referred to as

white matter

Microglia are (the)

smallest neuroglial cells

The effects of a neurotransmitter on the postsynaptic membrane include which of the following?

Excitatory or inhibitory responses.

If the point of an extremely small probe were passed into a satellite cell, it would be located in which region of the nervous system?

Near a cell body in a ganglion of the PNS

A group of neuron cell bodies in the CNS that has a descrete boundary is called a

Nucleus

Functions of the peripheral nervous system include

Providing sensory information to the CNS and carrying motor commands to the peripheral tissues and systems.

Receptors may be classified as

Somatic and visceral

nonvesicular synapses are unique because they have

a communicating junction

A neuron pool is

a group of interconnected neurons with specific functions

Action potentials result from

abrupt changing of the transmembrane potential

The process of reverberation involves

extension of collateral axons back toward the source of an impulse and further stimulation of the presynaptic neurons

Which of the following are most closely involved with somatic sensory neurons?

exteroceptors

A neuron might be temporarily unable to transmit an impulse to another if

its supply of neurotransmitters is exhausted

In the process known as Wallerian degeneration,

macrophages remove the debris of damaged axons

An inhibitory response

makes an action potential less likely

A biopsy of infected or injured tissue from the CNS will most likely show an elevated number of

microglia

Which of the following selections lists only types of glial cells?

microglia, oligodendrocytes, and Schwann cells

Myelin is (a)

mostly lipid

In the case of most neurons, the arrival of a nerve impulse at the terminal bouton immediately triggers

release of Ach at the presynaptic membrane

A communicating junction acts to facilitate

the passage of ions between the cells

the rate of conduction of a nerve impulse depends upon

the presence or absence of a myelin sheath

A nerve impulse triggers events at a synapse or junction that

transfer information either to another neuron or to an effector cell