An unidentified species of animal displays the following characteristics: bilateral symmetry, a complete digestive system, an open circulatory system, distinct body segmentation, and a series of molting stages during growth. To which of the following animal phyla does this species most likely belong?

In most insects, gas exchange is accomplished by __________.

In arthropods, molting is necessary because __________.

Sowbugs are really crustaceans, not insects. Therefore, a sowbug does not have __________.

The majority of animal species are __________.

Complete metamorphosis __________.

Which of the following animals is most closely related to spiders?

Which phylum is characterized by animals that have a segmented body?a. Cnidariab. Platyhelminthesc. Arthropodad. Mollusca

What is the function of the arthropod exoskeleton?a. The presence of an exoskeleton has given arthropods a good fossil record, because hard parts fossilize more readily than do soft tissues.b. It has no well-established function. (Trilobites had an exoskeleton, and they went extinct.)c. It provides protection and functions in locomotion.d. It makes growth by molting possible.