What is Action Potential?

Alie Astrocyte explains action potentials, starting with a recap of resting potential. She describes how a signal from another neuron can cause depolarization, where sodium ions rush into the cell, making it more positively charged. This signal moves down the neuron like a wave. After the signal passes, the cell repolarizes and hyperpolarizes, returning to its resting state. The entire process takes less than a millisecond. Alie hints at the next episode, which will cover how signals move between neurons.

What is the initial voltage change that triggers the opening of gated ion channels in a neuron?

• From -70 mV to -55 mV

• From -80 mV to -70 mV

• From -55 mV to -40 mV

• From -70 mV to -60 mV

During depolarization, which ions rush into the neuron causing a spike in electrical potential?

• Calcium ions

• Potassium ions

• Sodium ions

• Chloride ions

How does the signal move along the neuron during an action potential?

• Only towards the axon terminal

• Only towards the cell body

• In a specific order and direction

• Randomly in all directions

What happens to the neuron after the action potential has been fired and the sodium channels close?

• The neuron becomes positively charged

• The neuron immediately returns to resting potential

• The neuron becomes hyperpolarized

• The neuron remains depolarized

What role do potassium channels play after an action potential?

• They cause hyperpolarization

• They close sodium channels

• They maintain the resting potential

• They help depolarize the neuron