Ch 2: Nerve Cells And Nerve Impulses

Front 1

Neurons receive information and transmit it to other cells.

Back 1

True

Front 2

An afferent axon brings information into a structure.

Back 2

True

Front 3

Glial cells serve many functions.

Back 3

True

Front 4

Oligodendrocytes in the periphery are specialized types of glia.

Back 4

False, they are in the brain and spinal cord

Front 5

One disadvantage of the blood–brain barrier is that it keeps out most forms of nutrition.

Back 5

True

Front 6

At rest, the inside of a neuron's membrane is more negative than the outside.

Back 6

True

Front 7

Increasing the electrical gradient for potassium would reduce the tendency for potassium ions to exit the neuron.

Back 7

True

Front 8

The sodium–potassium pump is what normally brings the membrane back to its original state of polarization after the peak of the action potential.

Back 8

False;

Front 9

Additional stimulation beyond the threshold of excitation will result in a greater depolarization of the membrane during an action potential.

Back 9

False;

Front 10

Dendrites and cell bodies are capable of producing action potentials.

Back 10

False,

dendrites are branching fibers from a neuron that receive information from other neurons while cell bodies are structure containing the nucleus, ribosomes, and mitochondria

Front 11

The two kinds of cells in the nervous system are:

Back 11

neurons and glia.

Front 12

Santiago Ramon y Cajal demonstrated that:

Back 12

neurons are separate from one another.

Front 13

The structure that contains the chromosomes is called the:

Back 13

Nucleus

Front 14

The branching fibers that form the information–receiving pole of the nerve cells are called:

Back 14

Dendrites

Front 15

Which of the following is the correct order of transmission of information within a neuron?

Back 15

dendrite, cell body, axon

Front 16

Nodes of Ranvier are:

Back 16

gaps in the myelin of axons

Front 17

Chemicals are released by axons:

Back 17

into the junction between neurons.

Front 18

Which of these is true of glial cells?

Back 18

They do not transmit information over long distances.

Front 19

Which type of glia builds myelin sheaths around axons in the periphery of the body?

Back 19

Schwann cells

Front 20

What is the approximate resting potential of the inside of a neuron's membrane, relative to the outside?

Back 20

–70 millivolts

Front 21

The sodium–potassium pump repeatedly transports three ________ ions out of the cell while drawing two ________ ions into it.

Back 21

sodium; potassium

Front 22

What is one major cause for the resting potential of a neuron's membrane?

Back 22

the sodium–potassium pump

Front 23

The sodium gates in the axon are usually closed. Which of the following opens them?

Back 23

depolarization of the membrane

Front 24

Stimulus A depolarizes a neuron just barely above the threshold. Stimulus B depolarizes a neuron to 10 mV beyond threshold. What can we expect to happen?

Back 24

Stimulus A and stimulus B will produce the same response in the neurons because..

all-or-none lawprinciple that the amplitude and velocity of an action potential are independent of the stimulus that initiated it

Front 25

If depolarization is less than the cell's threshold:

Back 25

sodium crosses the membrane only slightly more than usual.

Front 26

Voltage–activated channels are channels for which a change in the voltage across the membrane alters their:

Back 26

permeability.

Front 27

At the peak of the action potential, the electrical gradient of potassium:

Back 27

pushes potassium out of the cell.

Front 28

The presence of an all–or–none law suggests that neurons can only convey different messages by changing their:

Back 28

rate or pattern of action potentials; To signal the difference between a weak stimulus and a strong stimulus, the axon can't send bigger or faster action potentials. All it can change is the timing. Similar to analogy or morse code!

Front 29

What will affect the speed of an action potential?

Back 29

the resistance of the membrane

Front 30

What are the nodes of Ranvier?

Back 30

gaps in the myelin sheath