Chondrichthyes: Cartilaginous Fish Feature Advantage Streamlined body & paired fins Enhances stability and maneuverability Paired gills Exchange O2 and CO2 Sharp, triangular teeth Tear apart prey Paired nostrils Smell and locate prey Lateral line A line of sensory cells along the side of the body that sense movement Placoid scales Give a sandpaper like texture to skin Spiracles (in skates and rays) Modified gill slits that help take on water when the animal’s mouth is buried in the sand. Osteichthyes: Bony Fish Characteristics Organ/ Structure Function Heart Pumps gases dissolved in the blood to the tissues of the body and to the swim bladder Blood vessels Carry gases to and from the swim bladder Swim bladder Fills with gases from the blood, making the fish more buoyant Caudal (tail) fin Propels the fish Dorsal fin Stabilizes the fish, keeping it upright Pectoral fins Used for movement and provides stability, preventing the fish from rolling over Olfactory Bulb Organ involved in sense of smell. Mr. Piwowarczyk