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WorksheetsReview 3.2 - 3.3: Neurons and Nerve Impulses
Total questions: 25
Worksheet time: 19mins
Neurons are used in the human body to transmit "messages" to ____.
Other neurons
Other cells in the body
Neurons and other cells in the body
The main "cell" part of a neuron is/are called the _____.
Axon
Cell body
Dendrites
Axon terminals
The _____ of a neuron branch off the cell body and receive nerve impulses from other neurons to funnel toward the cell body.
Dendrites
Axon terminals
Axon
Nodes of Ranvier
The _____ of a neuron is like a long "neck" that carries nerve impulses away from the cell body.
Dendrites
Axon terminals
Axon
Nodes of Ranvier
The _____ is / are small bulb-like structures at the end of an axon.
Dendrites
Axon terminals
Axon
Nodes of Ranvier
The _____ is / are a protective, fatty layer that surrounds the axon of a neuron.
dendrites
myelin sheath
gray matter
nodes of Ranvier
What is the purpose of the myelin sheath on an axon?
Protects the axon from ripping off the cell body of the neuron
Surrounds the axon to keep the cytoplasm and water inside the neuron
Insulates the axon to make a nerve impulse travel faster down the axon
The sections of uninsulated axon on a neuron are called _____.
nodes of Ranvier
nodes of Myelin
gaps of Ranvier
gaps of Myelin
____ is deeper in the brain and is composed of a lot of neurons with myelinated axons.
Gray matter
White matter
Pink matter
The area where the axon terminals of one neuron come in close proximity to the dendrites of another neuron is called the ____.
Neuronic divide
Synaptic cleft
Axonic canyon
In a neuron, the _____ is a difference in charge that exists across a cell's membrane.
Charge potential
Membrane potential
Cellular potential
When "resting," the outside of a neuron has an overall _____ charge.
Positive
Negative
When "resting," the outside of a neuron has a(n) _____ amount of sodium (Na+) ions.
Larger
Smaller
_____ allow sodium (Na+) and potassium (K+) ions to move freely across a membrane based on their concentration gradient.
Channel proteins
The sodium-potassium pump
Na+ and K+ gated channels
_____ only open to allow Na+ and K+ to cross the neuron's membrane during an action potential.
Channel proteins
The sodium-potassium pump
Na+ and K+ gated channels
A(n) _____ occurs when there is a change in the membrane potential and a neuron sends a "nerve impulse" along its axon.
Action potential
Ion potential
Neuron potential
Which section of this graph shows the membrane potential when a neuron is at rest?
Section A
Section C
Section E
Section F
Which section of this graph shows the membrane potential of a neuron during depolarization?
Section A
Section C
Section E
Section F
Which section of this graph shows the membrane potential of a neuron during repolarization?
Section A
Section C
Section E
Section F
During which time frame on the graph is the action potential occuring?
0 - 1 ms
1 - 2 ms
2 - 3 ms
3 - 4 ms
During an action potential, _____ occurs when Na+ gated channels open, Na+ enter the neuron, and the membrane potential becomes more positive.
The resting potential
depolarization
repolarization
hyperpolarization
During an action potential, _____ occurs when K+ gated channels open, K+ exit the neuron, and the membrane potential becomes more negative again.
The resting potential
depolarization
repolarization
hyperpolarization
What happens at the peak of an action potential?
Na+ gated channels close
Na+ gated channels open
K+ gated channels close
K+ gated channels open
Why can't a section of a neuron fire another nerve impulse right after an action potential?
Because the Na+ and K+ gated channels are blocked and cannot reopen
Because the sodium-potassium pump shuts down
Because there is no more ATP in the neuron for this process
True or False -- An action potential happens along the entire axon at one time.
True
False
