Excitable Quiz A

If a cell becomes more permeable to potassium, which way does the resting membrane potential move?

• Toward potassium’s equilibrium potential
• Away from potassium’s equilibrium potential
• No change
• Becomes positive

Which part of the neuron transmits the electrical signal from one end of the cell to the other?

• Dendrite
• Soma
• Axon
• Axon terminal

TRUE or FALSE: Open sodium channels accelerate the repolarization phase of an action potential.

• True
• False
• Depends on ion gradient
• Only in muscle cells

An excitatory post synaptic potential (EPSP) is:

• Depolarizing
• Repolarizing
• Hyperpolarizing
• None of the above

If the permeability of sodium were decreased, what would happen to the resting membrane potential?

• It would increase
• It would decrease
• It would increase then decrease
• No change

Which ion is used to refresh the action potential as it travels down the axon?

• Potassium
• Sodium
• Calcium
• Chloride

What ion allows neurotransmitters to be dumped into the synaptic cleft?

• Potassium
• Sodium
• Calcium
• Chloride

Where is an action potential generated in a neuron?

• Dendrite
• Soma
• Axon hillock
• Axon terminal

Graded potentials are used where in a neuron?

• Axon
• Dendrites
• Axon terminal
• Soma

What does myelin do to a neuron's action potential?

• Slows it down
• Blocks it
• Insulates and speeds it up
• Has no effect