In an experiment involving planar bilayers, a solution of table salt (sodium and chloride ions in water) is added on the left side of the membrane while pure water is added on the right side. After 30 minutes, the researchers test for the presence of ions on each side of the membrane. The right side tests negative for ions. What can you conclude?
A) The experiment failed.
B) The water somehow blocked the movement of ions across the membrane.
C) The left side would probably also test negative for ions.
D) Ions cannot cross planar bilayers.

Question

Quizplus · Accepted Answer

Planar bilayers are known to be impermeable to ions unless specific ion channels or pores are present. Since the ions did not cross to the right side, it suggests that in this experiment, the bilayer did not have such channels or pores, preventing ion movement across it.

In an Experiment Involving Planar Bilayers, a Solution of Table