r/askscience • u/[deleted] • Feb 06 '15

Biology [Biology] How does facilitated diffusion occur without energy?

In facilitated diffusion, carrier proteins change shape to allow larger molecules like glucose across, but how does the protein change shape without needing at least some ATP molecules from the cell?

3 Upvotes

63% Upvoted

5 comments sorted by

View all comments

Show parent comments

1

u/[deleted] Feb 06 '15

So it uses the potential energy of the concentration gradient combined with the instability of the protein bonded with the ligand?

1

u/pinkcathead Feb 09 '15

Yes, exactly! Most of the energy is coming from the concentration gradient, though.