In which of the following ways do potassium channels in the squid giant axon differ from sodium channels?

In which of the following ways do potassium channels in the squid giant axon differ from sodium channels?

In which of the following ways do potassium channels in the squid giant axon differ from sodium channels?



  1. The potassium channels pass only a few ions per second.
  2. The potassium channels show little voltage dependence.
  3. The summing of the individual potassium channels does not reconstruct the macroscopic current.
  4. Once the potassium channels open in response to a voltage step command, they tend to remain open.
  5. All of the above

Answer: 4