Among many new features found in the early vertebrates, one involved the development in the circulatory system of a ventral chambered , and cells for transporting oxygen in the blood called

All echinoderms have well-developed sensory systems with a 3-lobed brain

Write down the 5 major groups of living fishes.

Neural spines are modifications found in some extinct animals that apparently were used to impale their prey.

Hagfish have a number of odd characteristics including a low pressure circulatory system with four hearts. Write down two other unusual characteristics.

There are more freshwater and terrestrial species of echinoderms than all the marine species.

All sharks are carnivorous predators.

Arthropods are segmented animals.  Often segments are fused into functional groups. Such fused segments are called ______________

All sharks are carnivorous predators.

Some bony fishes are able to extract as much as _____________% of the oxygen passing over their gills.