Question

Which of the following does not require carrier molecules during transport through cell membranes?

• A. Simple diffusion
• B. Facilitated diffusion
• C. Na${}^{+}$- K${}^{+}$ transport
• D. Active transport of sugars and amino acids

Answer 1

The correct option is A Simple diffusion

Simple diffusion occurs according to the differences in the concentration gradient of molecules. Diffusion means the transport of materials from a region of higher concentration to a region of lower concentration. It does not require carrier molecules.

So, the correct answer is 'Simple diffusion'.