Question

Which method of transport in the plasma membrane does not require a carrier molecule?

• A. Facilitated diffusion
• B. Active transport
• C. Simple diffusion
• D. Na⁺-K⁺ pump

Answer 1

The correct option is C

Simple diffusion

Neutral solutes can move across the plasma membrane along the concentration gradient by the process of simple diffusion. As the solutes move along the concentration gradient, a carrier is not required.