3251.3.3 Action Potential

Front

What is an Action Potential?

Back

An action potential is a rapid, temporary change in the membrane potential of a neuron, allowing it to transmit signals along the axon.

Front

What occurs during depolarization of a neuron?

Back

During depolarization, sodium channels open, allowing sodium ions to flow into the neuron, making the inside more positive.

Front

What is the Resting Potential of a neuron?

Back

The resting potential is the electrical charge difference across the neuronal membrane when the neuron is not actively sending a signal, typically around -70mV.

Front

What happens during the Hyperpolarization phase?

Back

During hyperpolarization, the membrane potential becomes more negative than the resting potential, often due to the continued outflow of potassium ions.

Front

What channels open when a neuron reaches +30mV?

Back

When a neuron reaches +30mV, potassium channels open, leading to repolarization.

Front

What is the charge inside the axon when a neuron is at rest?

Back

The inside of the axon has a negative charge when the neuron is at rest.

Front

What role do sodium ions play in action potentials?

Back

Sodium ions are crucial for depolarization; their influx causes the membrane potential to rise.

Front

What is repolarization?

Back

Repolarization is the process of restoring the membrane potential to its resting state after depolarization.

Front

What is the significance of the threshold potential?

Back

The threshold potential is the critical level to which a membrane potential must be depolarized to initiate an action potential.

Front

What is the all-or-nothing principle in action potentials?

Back

The all-or-nothing principle states that once the threshold is reached, an action potential will occur fully; it does not vary in strength.