In biology, this "against the flow" movement is called , and it’s made possible by tiny, mighty molecular machines: active transport proteins . What Are Active Transport Proteins? Unlike channel proteins that simply open a door for molecules to fall through (diffusion), active transport proteins are bouncers with attitude . They grab specific molecules and physically pump them across the cell membrane—from low concentration to high concentration.
with a biology student or science enthusiast who needs to remember the difference between active and passive transport! Follow for more cell biology breakdowns. active transport protein
But what if the club needs to clear out trash from the crowded inside to the empty outside? Or what if the club needs to bring in more VIP ions even though the room is already stuffed? In biology, this "against the flow" movement is