Under what circumstances does membrane transport always require energy?
A) whenever a molecule is polar and is moved through a phospholipid bilayer membrane
B) whenever a solute needs to be moved from low concentration to high concentration through a phospholipid bilayer membrane
C) whenever a solute is charged, such as an ion, and is moved through a phospholipid bilayer membrane
D) whenever molecules are moved that are too large to pass through the phospholipid bilayer membrane

Question

Quizplus · Accepted Answer

This is the definition of active transport, which always require energy to move solutes against their concentration gradient.

Under What Circumstances Does Membrane Transport Always Require Energy