#2 Neurons and Action Potentials

What is the name of the electrical impulse that neurons send?

• Resistance

• Action potential

• Current

• Voltage

What is the resting membrane potential of a neuron?

• -70 mV

• -55 mV

• +40 mV

• +75 mV

What is the purpose of the sodium-potassium pump in a neuron?

• To open voltage-gated sodium channels

• To repolarize the membrane after an action potential

• To create a difference in charge between the inside and outside of the cell

• To increase the speed of conduction in myelinated axons

What happens when a neuron reaches its threshold potential?

• The neuron returns to its resting state

• The voltage-gated sodium channels open

• The neuron undergoes hyperpolarization

• The potassium ions flow out of the cell

What is the purpose of the refractory period in a neuron?

• To open voltage-gated potassium channels

• To increase the speed of conduction in myelinated axons

• To maintain the resting membrane potential

• To prevent signals from traveling in both directions down the axon

What is the purpose of myelin in the conduction of action potentials?

• To open voltage-gated sodium channels

• To maintain the resting membrane potential

• To increase the speed of conduction

• To repolarize the membrane after an action potential

What is the name for the gaps in the myelin sheath where action potentials can leap?

• Nodes of Ranvier

• Ligand-gated channels

• Voltage-gated channels

• Sodium-potassium pumps

What is the term for the temporary reversal of a membrane potential during an action potential?

• Graded potential

• Hyperpolarization

• Repolarization

• Depolarization

What determines the frequency of an action potential?

• The strength of the stimulus

• The speed of conduction

• The resting membrane potential

• The presence of myelin

What is the measure of potential energy generated by separated charges?

• Membrane potential

• Resistance

• Current

• Voltage

Tags

NGSS.HS-PS2-4