Chapter 12 Quiz

Which part of the neuron contains the nucleus?

Soma

What do all glial cells have in common?

They assist neurons in their respective functions

A neuron conducting an impulse from the CNS to the detrusor muscle of the urinary bladder would be classified as a(n) __________ neuron.

autonomic motor

The conductive segment of a neuron is its _______, a region that contains many _______ gated channels.

axon, voltage-

In order to trigger the release of neurotransmitter from a neuron terminal, calcium ions

bind to proteins on the surface of synaptic vesicles.

When a nerve impulse reaches the transmissive segment of a neuron,

calcium diffuses into the neuron and neurotransmitter is released by exocytosis.

Receptors are parts of the nervous system that allow it to

collect information

The main way acetylcholine is cleared from a synapse is by

degradation by an enzyme.

According to Ohm's law, current is

directly related to voltage and inversely related to resistance.

The nervous system controls the activity of muscles and glands. Muscles and glands can generate changes and are therefore called

effectors

Most commonly, a synapse is made between a

presynaptic neuron's axon and a postsynaptic neuron's dendrite.

The function of myelin is to

produce faster nerve impulse propagation.

One of the ways in which neurotransmitter is removed from the synaptic cleft is

reuptake by the presynaptic cell.

The afferent division of the nervous system is also known as the _____ division.

sensory

A mixed nerve is one that contains both

sensory and motor neurons

The portion of the nervous system that has voluntary control over skeletal muscles is the _____________ division.

somatic motor

The portion of the nervous system that conducts impulses from the skin, joints, skeletal muscles, and special senses is the ___________ division.

somatic sensory

In a mixed nerve

some axons transmit sensory information and others transmit motor information.

The electrochemical gradient refers to

the combination of electrical and chemical gradients between two areas.

The glossy-white appearance of most axons is due to

the high lipid content of the myelin sheath

Based on structure, the most common type of neuron is the _______ neuron.

unipolar

Continuous conduction of a nerve impulse occurs only along

unmyelinated axons.

A neuron conducting an impulse from the stomach wall to the CNS would be classified as a(n) __________ neuron.

visceral sensory

The separation of oppositely charged ionic particles across a resting neuron's membrane results in a potential that is measured as a

voltage

Action potentials are generated by the opening of ________ gated channels and they occur on the ________.

voltage-, axon

Typically, the resting membrane potential of a neuron is

−70 mV.

Nerves and ganglia are structures found in the

peripheral nervous system

Which choice correctly orders the connective tissue wrappings of a nerve, beginning at the outermost layer?

Epineurium → perineurium→ endoneurium

The primary inhibitory neurotransmitter in the brain is

GABA

What structures extend into the axon and dendrite of a neuron to provide tensile strength?

Neurofibrils

Which division of the nervous system shows a greater capacity for regeneration?

PNS

Conductive activity in a neuron generally causes it to secrete

a specific neurotransmitter that either excites or inhibits its target.

Hyperpolarization of a neuron results from

either the entry of an anion or the exit of a cation.

Which is not characteristic of neurons?

high mitotic rate

Potassium has a higher concentration

inside the cell versus outside the cell, whereas sodium has a higher concentration outside versus inside the cell.

The neurons that are responsible for integrating information by retrieving, processing, storing, and "deciding" how the body responds to stimuli are

interneurons

Which functional class of neurons lies entirely within the central nervous system?

interneurons

A nerve

is a cablelike bundle of parallel axons.

Which of the following is false regarding acetylcholine?

it is rarely used in the body

A depolarization is when the inside of a neuron becomes _______________ the resting membrane potential.

less negative than

A bipolar neurons has

one axon and one dendrite extending from the cell body.

Arrival of an action potential at the synaptic knob results in

opening of voltage-gated calcium channels and diffusion of calcium into the synaptic knob.