Chapter 12 Practice Questions

The nervous system employs exclusively electrical means to send messages, whereas the endocrine system communicates by means of chemical messengers.

Most neurons have multiple dendrites.

Neurons move material away from the soma by retrograde transport.

Unipolar neurons have only a single process leading away from the soma.

Oligodendrocytes serve the same purpose in the CNS that satellite cells do in the PNS.

Ependymal cells line the inner cavities of the CNS.

In the brain, neurons are more abundant than neuroglia.

An action potential never occurs in dendrites.

When a neuron is stimulated, Na+ gates open and allow Na+ to exit the cell.

In a myelinated fiber, only the initial segment in the trigger zone has voltage-regulated channels.

Norepinephrine is a monoamine.

Acetylcholine triggers the synthesis of the second messenger cAMP only in neurons of the PNS.

Nitric oxide (NO) acts as a neuromodulator by altering synaptic function.

Any two EPSPs will override one IPSP.

Memories are formed by neural pathways of modified synapses.

The __________ division carries signals to the smooth muscle in the large intestine.

The __________ division tends to prepare the body for action.

Which of the following are effectors?

What is another name for the autonomic nervous system?

Nerves are __________ of the nervous system.

Some __________ neurons are specialized to detect stimuli, whereas __________ neurons send signals to the effectors of the nervous system.

About 90% of the neurons in the nervous system are __________ neurons.

What is the most common type of neuron?

The term "nerve fiber" refers to a(n) __________.

Most metabolic and regulatory functions in a neuron happen where?

Which glial cell is found wrapped around nerve fibers in the PNS?

In which part of a neuron is the postsynaptic membrane usually found?

What is the primary site on a neuron for receiving signals from other neurons?

Which cells form myelin in the spinal cord?

A myelin sheath is composed primarily of __________.

Conduction of a nerve impulse would be the fastest in which of the following?

In order to regenerate, a peripheral nerve fiber must have which of the following?

Which of the following ions has the greatest influence on the resting membrane potential?

Where do most local potentials form in a neuron?

In a neuron, the opening of sodium gates typically leads to __________.

Which of the following will cause the plasma membrane to hyperpolarize when at its RMP?

Local potentials are __________, meaning they vary in magnitude according to the strength of the stimulus.

An inhibitory local potential causes which of the following?

While a neuron membrane is depolarizing its __________.

A neuron receives a stimulus. Which of the following events happens next?

In an action potential, which event directly follows repolarization?

Local potentials are __________, whereas action potentials are __________.

What occurs during hyperpolarization of a neuron membrane?

When the voltage of a plasma membrane shifts from +35mV towards 0 mV, the cell is __________.

During the absolute refractory period which of the following is true?

A traveling wave of excitation is known as a(n) __________.

What would be the best explanation for why myelinated fibers conduct signals faster than unmyelinated fibers?

All of the following are typical characteristics of neurotransmitters except __________.

A cholinergic synapse uses __________ as its neurotransmitter.

hat is the most common inhibitory neurotransmitter in the brain?

Which of these happens first in an cholinergic synaptic transmission?

Which of these happens first in an adrenergic synaptic transmission?

Some antidepressant drugs act by inhibiting monoamine oxidase (MAO). What is the function of this enzyme?

Which of these does not contribute to the cessation of the signal in a synaptic transmission?

Which neurotransmitter excites skeletal muscle and inhibits cardiac muscle?

Inhibitory postsynaptic potentials (IPSPs) are associated with which of the following?

The opening of __________ gates produces an __________.

Which of these is an example of an EPSP in a typical neuron?

A neuron can receive thousands of EPSPs from different neurons, and responds by triggering or not triggering an action potential. This addition and response to the net effect of postsynaptic potentials is called __________.

What is the opposite of presynaptic inhibition?

What type of neural circuit is best for producing a prolonged output?

Even though all action potentials are the same, the brain can differentiate a variety of stimuli by source and intensity. The mechanism by which the nervous system converts these action potentials into meaningful information is called neural __________.

Parkinson disease is a progressive loss of motor function due to the degeneration of specific neurons. These neurons secrete an inhibitory neurotransmitter that prevents excessive activity in motor centers of the brain. What neurotransmitter is this?

Accumulation of Ca2+ in the synaptic knob is called __________, and probably plays an important role in __________.

While both systems maintain homeostasis, how does the nervous system differ from the endocrine system?

Which body system(s) is(are) dedicated to maintaining stable internal conditions by detecting and responding to stimuli?

What property of neurons allows them to respond to changes in the environment?

If a neuron is prevented from sending a neurotransmitter across a synapse to another cell, which neuron property is being inhibited?

How does a neuron transport enzymes produced in the soma to its axon terminals?

Where are unmyelinated nerve fibers surrounded by Schwann cells?

Which of the following is true regarding unmyelinated nerve fibers in the PNS?

In PNS nerve fiber regeneration, how is a growing axon directed to its original destination?

If the potassium leak channels were suddenly blocked in a resting neuron, what would happen to its resting membrane potential?

Where does saltatory conduction occur?

Place the following events in synaptic transmission at a cholinergic synapse in order: A - A postsynaptic potential is produced; B - Voltage gated calcium channels open and calcium enters the cell; C - ACh is released and diffuses across the synaptic cleft; D - A nerve signal arrives at a synaptic knob; E - Ligand gated sodium channels open and sodium enters the cell.

Place the following events of synaptic transmission at an adrenergic synapse in order: A - ATP is converted to cAMP B - The cell's metabolism is altered C - G protein binds adenylate cylase D - The G protein dissociates E - NE binds the receptor

The respiratory center gathers information from a variety of sources in order to set the rate and depth of breathing. This is an example of what type of neural circuit?