Chapter 23.1-23.3 Review

All vertebrates are classified in the phylum

• mammalia

• agnatha

• chrodata

• reptilia

The earliest vertebrates were

• fish

• amphibians

• mammals

• reptiles

Hagfish are different from more evolved vertebrates because

• it is protected by a thick bony shell

• has a skeleton made of carilate

• does not have vertebrae

• lays eggs that can develop out of water

Four features all chordates share at some point in development

• notochord, hollow nerve cord, pharyngeal slits, tail

• hollow nerve cord, jaws, tail, pharyngeal slits

• tail, spinal cord, pharyngean slits, and fins

• jaws, tail, fins, and notochord

refers to an internal skeleton built of bone or cartilage

• exoskeleton

• vertebrae

• endoskeleton

• notochord

The gills of a fish serve what essential function?

• keep fish stable in water

• return blood to the heart

• take in oxygen from water

• prevent countercurrent flow

What structure did jaws evolve from?

• antennae

• gill arches

• front legs

• notochord

The two remaining groups of jawed fish that still exist are the

• osteichthyes and the agnatha

• osteichthyes and the chondrichthyes

• osteichthyes and the acanthodians

• chondrichthyes and acanthodians

How did the development of jaws affect vertebrates?

• improved their ability to filter feed

• gave them an advantage as predators

• enable them to obtain nutrients from coral

• made them more streamlined and faster

sensory system used by fish to detect movements of other fish in the water is called the

• countercurrent flow

• operculum

• lateral line

• swim bladder