A bidirectional cell is like a two-way street for cells in your body. You know how a street has lanes going in one direction and cars can only go that way? Well, cells usually only travel in one direction too, but a bidirectional cell is special because it can go both ways! It's like the cell can turn around and go back where it came from if it needs to. This is important because it helps cells communicate and work together to keep your body healthy. So just like cars need two-way streets to get where they need to go, some cells need bidirectional cells to get where they need to be in your body.