Final answer:
Coupling transport of a solute to the movement of a second solute can occur through symport mechanisms in the cell membrane, where two substances are moved in the same direction. This process requires energy and allows solutes to move against their concentration gradients.
Step-by-step explanation:
Coupling transport of a solute to the movement of a second solute can occur through symport mechanisms in the cell membrane. Symporters are secondary active transporters that move two substances in the same direction. For example, the sodium-glucose symporter uses sodium ions to "pull" glucose molecules into the cell, allowing glucose to move against its concentration gradient. This process requires energy and is facilitated by the movement of another solute down its concentration gradient.