The lophophore surrounds the mouth and is an upstream collecting system for suspension feeding. The gut is U-shaped with the anterior mouth at the center of the lophophore. The anus, where present, is also anterior, and is above the mouth. In the Bryozoa it is outside the ring of the lophophore; in the Entoprocta the anus is within the ring of the lophophore. Some brachiopods do not have an anus.