Chapters 11 & 12: True/False

Question 1

The all-or-none phenomenon as applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place

Answer 1

False

Question 2

Reflexes are rapid, automatic responses to stimuli.

Answer 2

True

Question 3

Efferent nerve fibers may be described as motor nerve fibers.

Answer 3

True

Question 4

Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.

Answer 4

True

Question 5

Myelination of the nerve fibers in the central nervous system is the job of the oligodendrocyte.

Answer 5

True

Question 6

During depolarization, the inside of a neuron’s membrane becomes less negative.

Answer 6

True

Question 7

Neurons in the CNS are organized into functional groups.

Answer 7

True

Question 8

Strong stimuli cause the amplitude of action potentials generated to increase.

Answer 8

False

Question 9

The oligdendrocytes can myelinate several axons.

Answer 9

True

Question 10

Enkephalins and endorphins are peptides that act like morphine.

Answer 10

True

Question 11

In myelinated axons the voltage-regulated sodium channels are concentrated at the nodes of Ranvier.

Answer 11

True

Question 12

A postsynaptic potential is a graded potential that is the result of a neurotransmitter released into the synapse between two neurons.

Answer 12

True

Question 13

Large-diameter nerve fibers conduct impulses much faster than small-diameter fibers.

Answer 13

True

Question 14

The nodes of Ranvier are found only on myelinated, peripheral neuron processes.

Answer 14

False

Question 15

Unipolar neurons have axons structurally divided into peripheral and central processes.

Answer 15

True

Question 16

A stimulus traveling toward a synapse appears to open calcium ion channels at the presynaptic end, which in turn promotes fusion of synaptic vesicles to the axonal membrane.

Answer 16

True

Question 17

If bacteria invaded the CNS tissue, microglia would migrate to the area to engulf and destroy them.

Answer 17

True

Question 18

The overlapping functions of the nervous system are sensory input, integration, and motor output.

Answer 18

True

Question 19

The autonomic nervous system is under voluntary control; whereas, the somatic nervous system is involuntary.

Answer 19

False

Question 20

Axon diameter and degree of myelination determine nerve impulse conduction velocity.

Answer 20

True

Question 21

The action potential is caused by permeability changed in the plasma membrane.

Answer 21

True

Question 22

Some neurotransmitters can be either excitatory or inhibitory, depending upon the receptor.

Answer 22

True