Question

Which of the following ion channels are always sensitive to small changes in electric charge?

A. stress-activated channels

B. ligand-gated channels with extracellular ligands

C. voltage-gated channels

D. ligand-gated channels with intracellular ligands

E. all of the above

Answer 1

The answer of the provided question is-

Voltage-gated ion channels are always sensitive to small changes in electric charge. So, the correct answer of the provided question is option no, "C" i.e. "Voltage -gated channels."

Because, The voltage -gated ion channels are the type of ion channels that activate (open) and deactivate(close) according to the (or as a response to the) changes in electrical charges (or electrical potentials) of the cell membrane. That means, the changes in electrical charges regulate this kind of ion channels. So, the voltage -gated ion channels are always sensitive to small changes in electric charge.

Stress- activated ion channels are the type of ion channels that activate(open) and deactivate(close) as a response to any mechanical stimulus (stress) such as pressure caused by touch, wave of sound ,etc. Ligand- gated channels with extra cellular ligands are the type of ion channels that activate (open) and deactivate(close) as a response to the binding of a certain molecule of ligand (such as neurotransmitter) to the ion channel protein (particularly at the extracellular domain of the ion channel protein). The ligand-gated ion channels with intracellular ligands are the type of ion channels that activate (open) and deactivate(close) as a response to the binding of a certain molecule of ligand (such as nucleotide) to the ion channel protein (particularly at the intracellular domain of the ion channel protein). So, the stress -activated ion channels, ligand -gated ion channels with extracellular ligands and ligand -gated ion channels with intracellular ligands are not sensitive to the small changes in electric charge. So, the options "A","B" and "D" are incorrect. The option "E" of the provided question is also incorrect because all the types of ion channels that are mentioned in other options are not sensitive to the small changes in electric charge except the voltage -gated ion channel. So, the option "E" i.e. "All of the above" is also incorrect.