sentence: Some cephalopods can adjust their body shape to move through the water more easily.
sentences_before: Oxygenated water is taken into the mantle cavity to the gills. By contracting the mantle's muscles, the water is pushed out through the siphon, made by a fold in the mantle. Motion of the cephalopods is usually backward as water is forced out forwards, but the siphon can be pointed in different directions.
concept_name: cephalopod
headings: Cephalopod Nervous system and behaviour Moving around