Marine Biology Chapter 10 || Already Graded A+.

What do all fish have in common and what did primitive fish lack? correct answers All fish have vertebrates and primitive fish lacked paired fins and jaws What are the two types of jawless fish and what do they have in common? correct answers hagfish and lampreys both lack jaws, paired appendages, scales and have cartilage instead of bone Hagfish correct answers are bottom dwelling has two dental plates with horny cusps with a single fang for grabbing prey eat live prey and scavenge produce milky fluid when disturbed ovaries and testies often occur in the same individual, but only one is functional Lampreys correct answers have an oral disk and rasping tounge to grasp prey and suck out fluid are anadromous (breed in streams) doesn't have to be the stream they hatched in larvae are called ammocoetes and anchor to the ground Cartilaginous Fishes correct answers sharks, skates, rays and chimaeras skeleton is cartilage has jaws and paired fins placoid scales are either holocephalans (chimaeras) or elasmobranchs (sharks) which are either streamlined like sharks or dorsoventrally flattened like rays sharks correct answers swim with powerful sweeps of the caudal fin have heterocercal tails (dorsal lobe is larger than ventral) males have claspers- modified pelvic fins for sperm transfer large liver for buoyancy spiraled digestive tract for efficency ventral mouth with replaceable teeth found in all oceans humans harvest for meat, fins, leather, cartilage and sport Skates and rays correct answers dorsalventral flattened bodies large pectoral fins attached to the head reduced dorsal and caudal fins eyes and spiracles (openings for water) on top of head gill slits on ventral side no anal fin pavement-like teeth to crush prey (benthic invertabrates) fished for food- none are threatened Skates- correct answers move by creating a wave from the front to the back