Deck 2: Nerve Cells and Nerve Impulses

Question 1

Glial cells serve many functions.

Answer 1

True

Question 2

An afferent axon brings information into a structure.

Answer 2

True

Question 3

Neurons receive information and transmit it to other cells.

Answer 3

True

Question 4

Glial cells transmit information across long distances.

Question 5

Oligodendrocytes in the periphery are specialized types of glia.

Question 6

Most chemicals can easily cross the cell membrane of a neuron.

Question 7

There are more glial cells than neurons in the human brain.

Question 8

The blood-brain barrier is made up of closely packed glial cells.

Question 9

The general rule among neurons is that the wider the branching, the fewer connections with other neurons.

Question 10

Neurons can have any number of dendrites, but no more than one axon.

Question 11

An efferent axon carries information away from a structure.

Question 12

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

Question 13

Dendrites contain the nuclei, ribosomes, mitochondria, and other structures found in most cells.

Question 14

The primary source of energy used by the brain is fat.

Question 15

Axons are covered with an insulating material called a myelin sheath.

Question 16

Schwann cells build the myelin sheaths in the periphery of the body.

Question 17

A small gap is usually present between neurons.

Question 18

The greater the surface area of a dendrite, the more information it can receive from other neurons.

Question 19

Astrocytes remove waste material created when neurons die and control the amount of blood flow to each brain area.

Question 20

Neurons are distinguished from other cells by their shape.

Question 21

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

Question 22

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

Question 23

Who was the first researcher to demonstrate that neurons are separate from one another?

A) Curt P. Richter
B) Santiago Ramon y Cajal
C) Charles S. Sherrington
D) Jose Delgado

Question 24

Dendrites and cell bodies are capable of producing action potentials.

Question 25

If a drug was given that temporarily inactivated the sodium-potassium pumps, action potentials would cease immediately.

Question 26

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

Question 27

The cell membrane is composed of two layers of:

A) protein.
B) fat.
C) carbohydrate.
D) plasma.

Question 28

The difference in voltage in a resting neuron is called the resting potential.

Question 29

Which of the following contributed most to Cajal's ability to find that neurons are separate from one another?

A) Charles Sherrington's study of reflexes
B) Camillo Golgi's cell staining method
C) Perves & Hadley's dye injection method
D) Galileo's invention of the telescope

Question 30

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

Question 31

What are the two kinds of cells in the nervous system?

A) neurons and glia
B) dendrites and axons
C) ribosomes and lysosomes
D) neurons and axons

Question 32

Prior to the work of Santiago Ramon y Cajal, what did many investigators believe?

A) Nerves conducted impulses at the speed of light.
B) Transmission across a synapse was just as fast as transmission along an axon.
C) The tip of an axon physically merged with the next neuron.
D) All neurons were of similar size and shape.

Question 33

A prolonged increase in the permeability of the membrane to sodium ions would interfere with a neuron's ability to have an action potential.

Question 34

Neurons differ most strongly from other body cells in their:

A) temperature.
B) shape.
C) osmotic pressure.
D) mitochondria.

Question 35

The ____ of neurons most strongly differentiate them from other cells in the body.

A) temperature.
B) shape.
C) osmotic pressure.
D) mitochondria.

Question 36

What structure is composed of two layers of fat molecules that are free to flow around one another?

A) the endoplasmic reticulum
B) a ribosome
C) a mitochondrion
D) the membrane

Question 37

Santiago Ramon y Cajal demonstrated that:

A) at rest, the neuron has a negative charge inside its membrane.
B) neurons are separate from one another.
C) neurons communicate at specialized junctions called synapses.
D) action potentials follow the all-or-none law.

Question 38

In a myelinated axon, sodium channels are absent in the nodes of Ranvier.

Question 39

The two kinds of cells in the nervous system are:

A) neurons and glia
B) dendrites and axons
C) ribosomes and lysosomes
D) neurons and axons

Question 40

Water, oxygen and ____ most freely flow across a cell membrane.

A) calcium
B) positively charged ions
C) magnesium
D) carbon dioxide

Question 41

The main feature that distinguishes a neuron from other animal cells is that a neuron has:

A) a larger nucleus.
B) a distinctive shape.
C) the ability to metabolize a variety of fuels.
D) a high internal concentration of sodium ions.

Question 42

Where do the metabolic activities occur that provide energy for all of the other activities of the cell?

A) Mitochondria
B) Ribosomes
C) Lysosomes
D) Golgi complexes

Question 43

The sites at which the cell synthesizes new protein molecules are called:

A) mitochondria.
B) endoplasmic reticula.
C) ribosomes.
D) plasma membranes.

Question 44

Some dendrites contain additional short outgrowths. What are these outgrowths called?

A) hillocks
B) dendritic spines
C) dendritic roots
D) myelin sheaths

Question 45

Protein channels allow ____ to cross the cell membrane.

A) large charged molecules
B) small charged molecules
C) large uncharged molecules
D) small uncharged molecules

Question 46

Many dendrites contain short outgrowths called spines that:

A) increase the surface area available for synapses.
B) increase the speed of transmission.
C) eliminate cell waste products.
D) increase the symmetry of the cell.

Question 47

Which of the following is NOT a characteristic of a dendrite?

A) It tapers as it gets further from the cell body.
B) It is in contact with the dendrites of other neurons.
C) Its surface may be lined with synaptic receptors.
D) It receives information from other neurons or the environment.

Question 48

Which of the following is most likely to cross the cell membrane by simple diffusion?

A) large proteins
B) small, charged ions
C) small, uncharged molecules
D) large, charged ions

Question 49

One of the most distinctive features of neurons compared to other types of cells is their:

A) shape.
B) number of mitochondria.
C) lack of a cell membrane.
D) size.

Question 50

Chemicals than cannot flow freely across a cell membrane enter a neuron through:

A) a Golgi complex.
B) specialized protein channels.
C) the endoplasmic reticulum.
D) gaps in the myelin sheath.

Question 51

The surface of a dendrite is lined with specialized junctions through which the dendrite receives information from other neurons. What are these junctions called?

A) synaptic receptors
B) axons
C) synaptic hillocks
D) glia

Question 52

Which chemicals flow most freely across a cell membrane?

A) proteins, fats, and carbohydrates
B) positively charged ions
C) water, oxygen, and carbon dioxide
D) calcium and magnesium

Question 53

Ribosomes are the part of a cell that:

A) performs metabolic activities.
B) breaks down harmful chemicals.
C) transports proteins.
D) synthesizes new proteins.

Question 54

Small, charged molecules can cross the cell membrane through:

A) diffusion.
B) ribosomes.
C) mitochondria.
D) protein channels.

Question 55

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

A) motor neurons.
B) dendrites.
C) sensory neurons.
D) axons.

Question 56

The structure that contains the chromosomes is called the:

A) endoplasmic reticulum.
B) nucleus.
C) mitochondrion.
D) ribosome.

Question 57

Dendrites ____.

A) contain the nucleus, ribosomes, and other structures found in most cells
B) are branching fibers that get narrower near their ends
C) is a thin fiber of constant diameter
D) are an insulating material that cover an axon

Question 58

What receives excitation from other neurons and conducts impulses to muscle or gland cells?

A) sensory neurons
B) motor neurons
C) dendrites
D) dendritic spines

Question 59

The endoplasmic reticulum is a:

A) network of thin tubes that transport newly synthesized proteins.
B) site where the cell synthesizes new protein molecules.
C) structure that separates the inside of the cell from the outside.
D) structure that contains the chromosomes.

Question 60

The tree-like branches of a neuron that receive information from other neurons are called:

A) axons.
B) dendrites.
C) soma.
D) myelin.

Question 61

Which of the following is NOT true of axons?

A) They can vary greatly in length.
B) They carry information toward the soma.
C) They release chemicals that cross the synapse.
D) Some of them are covered with myelin sheaths.

Question 62

Myelin covers:

A) all axons
B) most dendrites
C) some axons in vertebrates and none in invertebrates
D) all vertebrate axons and some invertebrate axons

Question 63

The information sender of the neuron, which conveys an impulse toward either other neurons or a gland or muscle, is called the:

A) axon.
B) dendrite.
C) soma.
D) myelin.

Question 64

A presynaptic terminal is also known as:

A) an end bulb
B) a node of Ranvier
C) myelin
D) a spine

Question 65

An axon has many branches, each of which swells at its tip. These are known as:

A) presynaptic terminals.
B) efferent axons.
C) afferent axons.
D) intrinsic neurons.

Question 66

Compared to dendrites, axons usually:

A) form the information-receiving pole of the neuron.
B) are shorter than the dendrites.
C) are covered with myelin.
D) taper in diameter toward their periphery.

Question 67

Gaps in the insulating material that surrounds axons are known as:

A) interpeduncular nuclei.
B) nodes of Ranvier.
C) myelin synapses.
D) presynaptic terminals.

Question 68

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

A) cell body, dendrite, axon
B) dendrite, axon, cell body
C) axon, cell body, dendrite
D) dendrite, cell body, axon

Question 69

Incoming synapses are primarily found on:

A) dendrites only.
B) cell bodies only.
C) axons only.
D) dendrites and cell bodies.

Question 70

Neurons typically have one ____, but many ____.

A) dendrite; axons
B) axon; dendrites
C) cell body; axons
D) dendrite; cell bodies

Question 71

Which of the following is NOT a characteristic of an axon?

A) It can be up to a meter long.
B) It has a constant diameter.
C) It carries information toward the cell body.
D) It may be covered with a myelin sheath.

Question 72

The insulating material which covers many vertebrate axons is called the:

A) dendrite.
B) myelin sheath.
C) cell body or soma.
D) presynaptic terminal.

Question 73

Dendrites often contain additional short outgrowths. These are believed to:

A) increase the surface area available for synapses.
B) increase the speed of transmission.
C) eliminate cell waste products.
D) help the cell maintain its shape.

Question 74

Chemicals are released by axons:

A) into the presynaptic terminal.
B) into the junction between neurons.
C) through the efferent terminals.
D) to the mitochondria.

Question 75

Nodes of Ranvier are:

A) gaps in the myelin of axons.
B) the same as the myelin sheath.
C) the spiny outgrowths on dendrites.
D) responsible for cell metabolism.

Question 76

An axon releases chemicals:

A) into the presynaptic terminal.
B) into the junction between neurons.
C) through the efferent terminals.
D) to the mitochondria.

Question 77

A neuron can have any number of ____, but no more than one ____.

A) dendrites; axon
B) axons; dendrite
C) cell bodies; axon
D) cell bodies; dendrite

Question 78

A greater amount of branching on dendrites allows them to:

A) manufacture more mitochondria.
B) have a larger surface area available for receiving information from other neurons.
C) increase their membrane permeability.
D) lower their resting potential.

Question 79

What does myelin cover?

A) all axons
B) most dendrites
C) some axons in vertebrates and none in invertebrates
D) all vertebrate axons and some invertebrate axons

Question 80

What is the point from which an axon releases chemicals into the synapse?

A) the myelin sheath
B) the presynaptic terminal
C) a dendritic spine
D) the endoplasmic reticulum