The process of transport proteins helping large molecules like glucose across the cell membrane is called facilitated diffusion.

Here's why:

* Facilitated: This term indicates that the movement of the molecule is aided by a protein, in this case, a transport protein.

* Diffusion: This term refers to the movement of molecules from a region of high concentration to a region of low concentration. While facilitated diffusion still follows the concentration gradient, it requires the help of a transport protein.

Important Note: Facilitated diffusion is a type of passive transport, meaning it does not require the cell to expend energy. This is because the movement of molecules is driven by the concentration gradient.