Complex sentence: Typical of bivalves, water is drawn over gills or ctenidium by the beating of cilia where oxygen from the water is absorbed and suspended food and other water-borne nutrients become trapped in mucus that is then transported to the mouth, digested and expelled as feces.
Split into simpler sentences: Typical of bivalves, water is drawn over gills or ctenidium by the beating of cilia where oxygen from the water is absorbed. Suspended food and other water-borne nutrients also become trapped in mucus, which is then transported to the mouth, digested and expelled as feces.