A And P Ii Chapter 19

Front 1

Compared with the inside of the cell, the outside of most cell membranes is?

Back 1

Positive

Front 2

The difference in electrical charge across a plasma membrane is called?

Back 2

Membrane potential

Front 3

A neuron’s resting membrane potential is

Back 3

-70mV

Front 4

Which of the following statements is true concerning the sodium-potassium pump?

Back 4

Three sodium ions are pumped out of the neuron for every two potassium ions pumped into the neuron

Front 5

A membrane that exhibits a membrane potential is said to be polarized?

Back 5

True

Front 6

A slight shift away from the resting membrane potential in a specific region of the plasma membrane is often called a stimulus-gated channel?

Back 6

False

Front 7

Chlorine ions (CI) are the dominant extracellular cations?

Back 7

False

Front 8

During a relative refractory period:

Back 8

An action potential is possible only in response to a very strong stimulus

Front 9

Voltage-gated channels are?

Back 9

Ion channels that open in response to voltage fluctuations

Front 10

When current leaps across an insulating myelin sheath from node of Ranvier to node of Ranvier, the type of impulse conduction is?

Back 10

Saltatory conduction

Front 11

The larger diameter of a nerve fiber:

Back 11

The faster the speed of conduction

Front 12

Action potential and nerve impulse are synonymous?

Back 12

True

Front 13

When repolarization has occurred, an impulse cannot be conducted?

Back 13

False

Front 14

The action potential is an all-or-none response?

Back 14

True

Front 15

Many anesthetics function by inhibiting the opening of sodium channels and thus blocking the initiation and conduction of nerve impulses?

Back 15

True

Front 16

Which of the following structures is not a main component of a chemical synapse?

Back 16

Synaptic process

Front 17

A synaptic knob is located on the?

Back 17

Axon

Front 18

Which of the following is true of spatial summation?

Back 18

Neurotransmitters released simultaneously from several presynaptic knobs converge on one postsynaptic neuron

Front 19

In an adult, the nervous system is replete with both electrical synapse and chemical synapses?

Back 19

False

Front 20

Rapid-succession stimulation of a postsynaptic neuron by a synaptic knob can have a cumulative effect over time that can result in an action potential?

Back 20

True

Front 21

Ca++ ions cause the release of neurotransmitters across the synaptic cleft?

Back 21

True

Front 22

Neurotransmitters are released in a synapse and bind to?

Back 22

Receptors on the postsynaptic terminal

Front 23

The main chemical classes of neurotransmitters include all of the following except

Back 23

Norepinephrine

Front 24

Which of the following is not a example of an amine neurotransmitter

Back 24

Glycine

Front 25

Severe depression can be caused by a deficit in which of the following neurotransmitters?

Back 25

Amines

Front 26

Which of the following is not a catecholamine?

Back 26

Serotonin

Front 27

Many biologists now believe that neuropeptides are the most common neurotransmitters in the CNS?

Back 27

False

Front 28

Cocaine produces a temporary feeling of well-being by blocking the reuptake of dopamine?

Back 28

True

Front 29

Multiple sclerosis is a myelin disorder?

Back 29

True

Front 30

Physical injury, causing nerve damage, can cause local, or widespread loss of sensation and/or motor control?

Back 30

True

Front 31

Nerve conduction does not occur due to the fluctuations in the concentration of ions?

Back 31

False

Front 32

Myasthenia gravis is a bacterial disorder?

Back 32

False

Front 33

Parkinson disease is a failure to release adequate dopamine at the synapse of certain motor pathways?

Back 33

True

Front 34

The function of a neurotransmitter is determined by the postsynaptic receptor?

Back 34

True

Front 35

Neurotrophins stimulate neuron development but also can act as neurotransmitters or neuromodulators?

Back 35

True

Front 36

Neuroscience has advanced to a point at which the neuron doctrine has been expanded to include concepts of the _____________________

Back 36

reticular theory

Front 37

The concentration of neurotransmitters at synapses in certain neural pathways can affect ___________?

Back 37

Health

Front 38

_____________are nerve growth factors that are released by various cells of the body

Back 38

neurotrophins

Front 39

When more than one presynaptic axon synapses with a single postsynaptic neuron, ___________ occurs

Back 39

convergence

Front 40

When a single presynaptic axon synapses with many different postsynaptic neurons, _________occurs

Back 40

divergence

Front 41

A wave of electrical fluctuation that travels along the plasma membrane is called a __________

Back 41

Nerve Impulse

Front 42

The membrane potential maintained by a non-conducting neuron’s plasma membrane is called the ________ ________ ________

Back 42

resting membrane potential

Front 43

Movement of the membrane potential away from zero (thus below the usual RMP) is called _______?

Back 43

hyperpolarization

Front 44

Three structures make up a chemical synapse they are _______ _______, _______ _______, and the _________ ________

Back 44

synaptic knob, synaptic cleft, the plasma membrane of a postsynaptic neuron

Front 45

Long term memories (months or years) require ________ changes in the synapse, such as more vesicles or more vesicle release sites.

Back 45

structural

Front 46

The unique neurotransmitter that combines acetate with choline is acetylcholine. It is deactivated by _______?

Back 46

actylcholinesterase

Front 47

An example of a catecholamine is _______________?

Back 47

Dopamine, epinephrine, or norepinephrine

Front 48

Two major function classifications of neurotransmitters are excitatory neurotransmitters and ________?

Back 48

Inhibitory neurotransmitters

Front 49

A synaptic knob is a tiny bulge at the end of the __________neuron’s axon

Back 49

presynaptic

Front 50

Acetylcholine is an example of a __________

Back 50

neurotransmitter

Front 51

Neurotransmitters are chemicals that allow neurons to ____________with one another.

Back 51

communicated

Front 52

Neurotransmitters are distributed _______into groups of neurons.

Back 52

specifically

Front 53

Endorphins and enkephalins are neurotransmitters that inhibit conduction of _________

Back 53

pain

Front 54

A synonym commonly used for action potential is _______.

Back 54

nerve impulse

Front 55

In myelinated fibers, action potentials in the membrane occur only at the nodes of Ranvier. This type of impulse conduction is called __________.

Back 55

saltatory conduction

Front 56

A membrane that exhibits a membrane potential is said to be__________

Back 56

polarized

Front 57

A membrane that exhibits a membrane potential is said to be

Back 57

polarized.

Front 58

The membrane potential maintained by a nonconducting neuron's plasma membrane is called the _____ membrane potential.

Back 58

resting

Front 59

The mechanisms that produce and maintain the resting membrane potential do so by producing a

Back 59

slight excess of positive ions on the outer surface of the plasma membrane.

Front 60

The active transport mechanism in the plasma membrane that transports sodium and potassium ions in opposite directions and at different rates is the

Back 60

sodium-potassium pump.

Front 61

An ion channel that opens in response to a sensory stimulus is a(n)

Back 61

stimulus-gated channel.

Front 62

Movement of the membrane potential away from zero (below the usual RMP) is called

Back 62

hyperpolarization.

Front 63

A term commonly used as a synonym for action potential is

Back 63

nerve impulse.

Front 64

If the magnitude of the local depolarization surpasses a limit called the _____, voltage-gated Na+ channels are stimulated to open.

Back 64

threshold potential

Front 65

The brief period during which a local area of an axon's membrane resists re-stimulation is called the __________ period.

Back 65

refractory

Front 66

The action potential seems to "leap" from node to node along a myelinated fiber. This type of impulse regeneration is called __________ conduction.

Back 66

salutatory

Front 67

There are two types of synapses—the electrical synapse and the __________ synapse.

Back 67

chemical

Front 68

The tiny bulge at the end of a terminal branch of a presynaptic neuron's axon is called a(n)

Back 68

synaptic knob.

Front 69

What mechanism quickly terminates the action of a neurotransmitter once it binds to its postsynaptic receptor?

Back 69

Neurotransmitter molecules are transported back into synaptic knobs. Neurotransmitter molecules are metabolized into inactive compounds. Neurotransmitter molecules are transported into nearby glial cells.

Front 70

When synaptic knobs stimulate a postsynaptic neuron in rapid succession, their effect can add up over a brief period to produce an action potential. This is called

Back 70

temporal summation.

Front 71

Which chemicals allow neurons to communicate with one another?

Back 71

neurotransmitters