Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

bio 168 > chapter 11: the nervous system > Flashcards

chapter 11: the nervous system Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What division of the nervous system is most specifically responsible for voluntary motor control?

A

Somatic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which of the following is NOT one of the basic functions of the nervous system?
A. Decode sensory information from the environment.
B. Integrate sensory input for decision making. C. Generate direct, electrical signals.
D. Release hormones into the bloodstream that travel around the systemic blood circulation to communicate with cells in multiple locations within the body.

A

D. Release hormones into the bloodstream that travel around the systemic blood circulation to communicate with cells in multiple locations within the body.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

As you start working out, you notice that your heart rate and breathing rate start to increase. Which division of your nervous system is generating this response? Be as specific as possible.

A

The sympathetic division of the autonomic nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which glial cells have the most diversity of function?

A

astrocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

__________ ______ monitors the health of neurons, and can transform into a special type of macrophage to protect endangered neurons.

A

microglial cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Ependymal cells line many open cavities in the central nervous system (CNS). Ependymal cells have cilia on the side of the cell that face these openings. What is the most likely function of these ciliated cells?

A. movement and circulation of cerebrospinal fluid
B. create myelin sheaths for CNS cells
C. act as macrophage cells to destroy microorganisms or neuronal debris
D. exchange of nutrients between the circulatory system and neurons

A

A. movement and circulation of cerebrospinal fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What peripheral nervous system (PNS) neuroglia form the myelin sheaths around larger nerve fibers in the PNS?

A

Schwann cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the structure at A?

A

dendrites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What structural classification describes this neuron?

A

multipolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which areas of this neuron would be classified as receptive regions?

A

Both A and B

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which of these materials or structures would be found in greatest amounts or numbers at E?

A

vesicles containing neurotransmitter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

In which area of the neuron is an action potential initially generated?

A

C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which is the main receptive portion of the neuron

A

the dendrite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which of the following pairings does not fit?

A. multipolar neurons: peripheral nervous
B. system sensory neurons
association neuron: interneurons
C. motor neurons: efferent neurons.
D. sensory neurons: afferent neurons

A

A. multipolar neurons: peripheral nervous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Many neurons have many short, branching extensions called dendrites. What is the benefit of these structures for a neuron?

A

The dendrites provide a large surface area for connections from other neurons.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

A neuron can have _____ _____ axon, but the axon may have occasional branches along its length

A

only one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Which criterion is used to functionally classify neurons?

A

the direction in which the nerve impulse travels relative to the central nervous system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

In the motor division of the PNS, the effector organs consist of the three types of muscle tissue and glands. Which of these effector organs would be under voluntary control and thereby fall into the somatic nervous system?
A. Cardiac muscle
B. Skeletal muscle
C. Smooth muscle
D. Glands

A

B. Skeletal muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Which of the following membrane regions would have significant numbers of voltage-gated ion channels?

A

C and D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the basic condition when a neuron is described as polarized?

A

There is a separation of positive and negative charges across a membrane.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which of the following statements is correct regarding the polarization of a neuronal membrane and the formation of a resting membrane potential?
A. A resting potential can be generated without the energy as an input.
B. As Na+ leaks across the membrane, that establishes a negative charge inside the membrane.
C. As sodium leaks into the cell, the inside of the cell becomes more negative.
D. Sodium/Potassium pumps maintain concentration gradients; sodium and potassium move down their concentration gradients through leakage channels.

A

D. Sodium/Potassium pumps maintain concentration gradients; sodium and potassium move down their concentration gradients through leakage channels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which of the following does NOT describe conditions that occur during an action potential?
A. After initial depolarization, K+ now has both an electrical and a chemical gradient drawing it out of the cell.
B. Na+ is used to repolarize the membrane.
C. The Na+/K+ pump reestablishes resting concentration gradients.
D. Na+ enters the cell through voltage-gated channels, causing a reversal of the resting membrane potential.

A

B. Na+ is used to repolarize the membrane.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Which of the following events would be directly affected if a neuron had a mutation that prevented the production of voltage-gated Na+ channels?
A. generating the resting membrane potential
B. graded hyperpolarization
C. depolarization leading to action potentials
D. graded depolarization

A

C. depolarization leading to action potentials

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What type of event is required for an action potential to be generated?

A

A threshold level evaporation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Which of the following is NOT a difference between graded potentials and action potentials?
A. The magnitude of action potentials decrease as the impulse travels further away from the start of the impulse while graded potentials do not decrease in magnitude.
B. Graded potentials can result from the opening of chemically gated channels; action potentials require the opening of voltage-gated channels.
C. Greater stimulus intensity results in larger graded potentials, but not larger action potentials.
D. Graded potentials occur along dendrites, whereas action potentials occur along axons.

A

A. The magnitude of action potentials decrease as the impulse travels further away from the start of the impulse while graded potentials do not decrease in magnitude.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is a factor that determines the rate of impulse propagation, or conduction velocity, along an axon?

A

The degree of myelination of the axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What ion is entering the axon terminal at A, and what effect does it have?

A

Ca2+, which then causes release of neurotransmitter from the axon terminal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

By which method does the structure at B release neurotransmitter

A

exocytosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which of the following statements most accurately describes the effect caused by binding of the neurotransmitter (green dots) to the structure labeled C?

A

The membrane potential of the postsynaptic membrane changes.

30
Q

How would the receptors at C best be classified?

A

chemically gated

31
Q

Which of the following statements is true of both membrane potential responses shown in the graphs?

A

Both responses are examples of graded potentials

32
Q

Which of the following stimuli caused the reaction in the graph on the left

A

opening of gated Na+ channels

33
Q

Which of the following is expected to occur first if the membrane potential increase shown in the graph on the left were to reach the threshold value indicated at −55 mV?

A

opening of voltage-gated Na+ channels

34
Q

Suppose that both stimuli seen in these graphs happened equally at the same time on a postsynaptic membrane as a result of two different synapses. Which of the following best describes the result?

A

there would be little to no graded potential

35
Q

Which membrane potential occurs because of the influx of Na+ through chemically gated channels in the receptive region of a neuron?

A

excitatory postsynaptic potential

36
Q

Which of the following does NOT describe the process of summation?

A. One EPSP and one IPSP cancel each other out.
B. Two EPSPs are generated at the same time by two separate synapses, bringing the cell to threshold.
C. Two EPSPs occur close enough in time to bring the cell to threshold.
D. One EPSP fails to bring the cell to threshold.

A

D. One EPSP fails to bring the cell to threshold.

37
Q

What component of the reflex arc determines the response to a stimulus?

A

integration center

38
Q

Structures of the nervous system surrounding, but not part of the central nervous system are part of the
___________ __________ _________.

A

peripheral nervous system

39
Q

Supporting cells of the nervous system are collectively called
__________.

A

neuroglia

40
Q

When potassium channels have been open long enough to go below resting membrane potential, _____________ has occurred.

A

hyperpolarization

41
Q

When a neuron is stimulated and sodium channels open, the process of ___________ has begun

A

depolarization

42
Q

___________ are a group of natural chemicals that reduce the perception of pain.

A

endorphins

43
Q

Two consecutive neurons communicate at a
_______ , where they physically come together.

A

synapse

44
Q

The membranes of neurons at rest are very permeable to _____ but only slightly permeable to _____.

A

K+; Na+

45
Q

During depolarization, which gradient(s) move(s) Na+ into the cell?

A

both electrical and chemical gradients

46
Q

What is the value for the resting membrane potential for most neurons?

A

-70mv

47
Q

The Na+–K+ pump actively transports both sodium and potassium ions across the membrane to compensate for their constant leakage. In which direction is each ion pumped?

A

Na+ is pumped out of the cell and K+ is pumped into the cell

48
Q

The concentrations of which two ions are highest outside the cell.

A

Na+ and Cl–

49
Q

On average, the resting membrane potential is -70 mV. What does the sign and magnitude of this value tell you?

A

The inside surface of the plasma membrane is much more negatively charged than the outside surface.

50
Q

The plasma membrane is much more permeable to K+ than to Na+. Why?

A

There are many more K+ leak channels than Na+ leak channels in the plasma membrane.

51
Q

The resting membrane potential depends on two factors that influence the magnitude and direction of Na+ and K+ diffusion across the plasma membrane. Identify these two factors.

A

The presence of concentration gradients and leak channels

52
Q

What prevents the Na+ and K+ gradients from dissipating?

A

Na+-K+ ATPase

53
Q

Select the correct statement regarding synapses.
a. Cells with gap junctions use chemical synapses.
b. The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another.
c. The release of neurotransmitter molecules gives cells the property of being electrically coupled.
d. Neurotransmitter receptors are located on the axons terminals of cells.

A

b. The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another.

54
Q

The effect of acetylcholine can be stimulating or inhibiting. Which of the following gives the best explanation for why this is so?
a. Postsynaptic cells have a dynamic and changing metabolism and respond differently at different times.
b. Acetylcholine has a “dose effect”. Larger doses are stimulating while small doses inhibit.
c. Acetylcholine has many different forms.
d. Different post synaptic cells will have different receptors.

A

d. Different post synaptic cells will have different receptors.

55
Q

If a post synaptic cell is stimulated to threshold by temporal summation this implies that ________.
a. the presynaptic neuron is sending frequent IPSP
b. a presynaptic neuron is sending frequent EPSP
c. the postsynaptic cell is sending frequent action potential
d. the postsynaptic cell can be influenced by only one presynaptic cell

A

b. a presynaptic neuron is sending frequent EPSP

56
Q

True or False:
Strong stimuli cause the amplitude of action potentials generated to increase.

A

False

57
Q

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

A

True

58
Q

Which of the following is not characteristic of neurons?
a. They have an exceptionally high metabolic rate.
b. They have extreme longevity.
c. They conduct impulses.
d. They are mitotic.

A

d. They are mitotic.

59
Q

Which of the following describes the nervous system integrative function?
a. analyzes sensory information, stores information, makes decisions
b. responds to stimuli by gland secretion or muscle contraction
c. senses changes in the environment

A

a. analyzes sensory information, stores information, makes decisions

60
Q

During the relative refractory period of an action potential, a larger than normal stimulus is needed to cause another action potential. This is due to the fact that ________.
a. the inactivation gates on voltage gated sodium ion channels are closed
b. the voltage gated potassium ion channels remain open long enough to hyperpolarize the axon membrane
c. the membrane is now impermeable to all ions
d. the sodium potassium pump will stop working during relative refractory

A

b. the voltage gated potassium ion channels remain open long enough to hyperpolarize the axon membrane

61
Q

True or False:
Axon diameter and degree of myelination determine nerve impulse conduction velocity.

A

True

62
Q

Nerve impulses leading to the skeletal muscle carry information to direct movement. The nerve fibers sending these signals will most likely belong to which division of the nervous system?
a. sensory (afferent) division
b. somatic nervous system
c. sympathetic division
d. parasympathetic division

A

b. somatic nervous system

63
Q

Loss of function in the enzyme acetylcholine esterase would result in which of the following?
a. inability to release acetylcholine
b. stimulation of the production of acetylcholine
c. amplify or enhance the effect of ACh
d. inability to destroy and remove acetylcholine from the synaptic cleft

A

d. inability to destroy and remove acetylcholine from the synaptic cleft

64
Q

A neuron that has as its primary function the job of connecting other neurons is called a/n ________.
a. glial cell
b. efferent neuron
c. interneuron
d. afferent neuron

A

c. interneuron

65
Q

Which of the following is not true of graded potentials?
a. They can be called postsynaptic potentials.
b. They are short-lived.
c. They increase amplitude as they move away from the stimulus point.
d. They can form on receptor endings.

A

c. They increase amplitude as they move away from the stimulus point.

66
Q

The depolarization phase of an action potential is punctuated by the closing of inactivation gates in the voltage gated sodium ion channels. All of the following are consequences of this inactivation except one. Choose the statement below that is not a consequence of the closing of inactivating gates.
a. This limits the frequency of action potentials down the axon.
b. This allows for the efflux (diffusion out) of potassium ions, resulting in the repolarization of the cell.
c. This stops the depolarization of the axon membrane.
d. This allows for the one way transmission of action potential down the axon.

A

b. This allows for the efflux (diffusion out) of potassium ions, resulting in the repolarization of the cell.

67
Q

Which of the following is false or incorrect?
a. A nerve impulse occurs if the excitatory and inhibitory effects are equal.
b. An excitatory postsynaptic potential occurs if the excitatory effect is greater than the inhibitory effect but less than threshold.
c. An inhibitory postsynaptic potential occurs if the inhibitory effect is greater than the excitatory, causing hyperpolarization of the membrane.

A

a. A nerve impulse occurs if the excitatory and inhibitory effects are equal.

68
Q

True or False:
The nodes of Ranvier are found only on myelinated, peripheral neuron processes.

A

False

69
Q

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?
a. cholinesterase
b. norepinephrine
c. gamma aminobutyric acid
d. acetylcholine

A

d. acetylcholine

70
Q

True or False:
The action potential is caused by permeability changes in the plasma membrane.

A

True

71
Q

Schwann cells are functionally similar to ________.
a. oligodendrocytes
b. ependymal cells
c. microglia
d. astrocytes

A

a. oligodendrocytes

72
Q

Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters are ________.
a. astrocytes
b. Schwann cells
c. microglia
d. oligodendrocytes

A

a. astrocytes

bio 168 (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions