Final answer:
A carrier that carries only one type of solute is called a uniport. A uniporter is a carrier protein that transports only one specific ion or molecule across the membrane.
Step-by-step explanation:
A carrier that carries only one type of solute is called a uniport. A uniporter is a carrier protein that transports only one specific ion or molecule across the membrane. It is different from a symporter, which carries two different molecules or ions in the same direction, and an antiporter, which carries two different molecules or ions in different directions.