Chapter 11 Part 9 (multiple choice) Flashcards Preview

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Flashcards in Chapter 11 Part 9 (multiple choice) Deck (22):
1

The term central nervous system refers to the ________.
A) brain and spinal cord
B) brain, spinal cord, and peripheral nerves
C) spinal cord and spinal nerves
D) peripheral and spinal nerves

A) brain and spinal cord

2

The substance released at axon terminals to propagate a nervous impulse is called a(n) ________.
A) cholinesterase
B) ion
C) neurotransmitter
D) biogenic amine

C) neurotransmitter

3

A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.
A) afferent neuron
B) glial cell
C) association neuron
D) efferent neuron

C) association neuron

4

Saltatory conduction is made possible by ________.
A) large nerve fibers
B) erratic transmission of nerve impulses
C) the myelin sheath
D) diphasic impulses

C) the myelin sheath

5

Which of the following is not a chemical class of neurotransmitters?
A) nucleic acid
B) biogenic amine
C) acetycholine
D) ATP and other purines
E) amino acid

A) nucleic acid

6

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

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

7

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

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

8

Which of the following correctly describes a graded potential?
A) long distance signaling
B) voltage stimulus to initiate
C) voltage regulated repolarization
D) amplitude of various sizes

D) amplitude of various sizes

9

Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters are ________.
A) microglia
B) oligodendrocytes
C) astrocytes
D) Schwann cells

C) astrocytes

10

Schwann cells are functionally similar to ________.
A) astrocytes
B) oligodendrocytes
C) microglia
D) ependymal cells

B) oligodendrocytes

11

Immediately after an action potential has peaked, which cellular gates open?
A) calcium
B) chloride
C) sodium
D) potassium

D) potassium

12

Nerve cell adhesion molecules (N-CAMs) ________.
A) release nerve growth factor
B) are crucial in the production of neurotransmitters
C) are found on "pathfinder" neurons
D) are crucial for the development of neural connections

D) are crucial for the development of neural connections

13

An inhibitory postsynaptic potential (IPSP) is associated with ________.
A) lowering the threshold for an action potential to occur
B) hyperpolarization
C) a change in sodium ion permeability
D) opening of voltage-regulated channels

B) hyperpolarization

14

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?
A) Specific potassium gates will open.
B) Sodium gates will open first, then close as potassium gates open.
C) Specific sodium gates will open.
D) A single type of channel will open, permitting simultaneous flow of sodium and potassium.

D) A single type of channel will open, permitting simultaneous flow of sodium and potassium.

15

When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________.
A) action potential
B) generator potential
C) postsynaptic potential
D) excitatory potential

B) generator potential

16

Which of the following is not true of graded potentials?
A) They are short-lived.
B) They can form on receptor endings.
C) They can be called postsynaptic potentials.
D) They increase amplitude as they move away from the stimulus point.

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

17

Which of the following is true about the movement of ions across excitable living membranes?
A) Ions always move from an area of higher concentration to an area of lower concentration
B) Ions always move actively across membranes through leakage channels.
C) Sodium gates in the membrane can open in response to electrical potential changes.
D) Ions always move passively across membranes.

C) Sodium gates in the membrane can open in response to electrical potential changes.

18

A second nerve impulse cannot be generated until ________.
A) the Na ions have been pumped back into the cell
B) all sodium gates are closed
C) proteins have been resynthesized
D) the membrane potential has been reestablished

D) the membrane potential has been reestablished

19

In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is ________.
A) negatively charged and contains more sodium
B) negatively charged and contains less sodium
C) positively charged and contains more sodium
D) positively charged and contains less sodium

B) negatively charged and contains less sodium

20

If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon ________.
A) the impulse would spread bidirectionally
B) muscle contraction would occur
C) the impulse would move to the axon terminal only
D) the impulse would move to the axon terminal only, and the muscle contraction would occur

A) the impulse would spread bidirectionally

21

Which of the following neurotransmitters inhibits pain and is mimicked by morphine, heroin, and methadone?
A) nitric oxide
B) endorphin
C) acetylcholine
D) serotonin

B) endorphin

22

Which of the following describes the excitatory postsynaptic potential?
A) short distance hyperpolarization
B) moves membrane potential away from threshold
C) opens K+ or Cl- channels
D) short distance depolarization

D) short distance depolarization