A land snail, a clam, and an octopus all share

a. A mantle

b. A radula

c. Gills

d. Distinct cephalization

Which phylum is characterized by animals that have a segmented body?

a. Cnidaria

b. Platyhelminthes

c. Arthropoda

d. Mollusca

The water vascular system of echinoderms

a. Functions as a circulatory system that distributes nutrients to body cells

b. Functions in locomotion and feeding

c. Is bilateral in organization, even though the adult animal is not bilaterally symmetrical

d. Moves water through the animal's body during filter feeding

Which of the following combinations of phylum and description is correct?

a. Echinodermata—radial symmetry as a larva, coelom

b. Nematoda—roundworms, internal skeleton

c. Platyhelminthes—flatworms, gastrovascular cavity, no body cavity

d. Porifera—gastrovascular cavity, coelom

In the following figure, which two main clades branch from the most recent common ancestor of the eumetazoans?

a. Porifera and Cnidaria

b. Lophotrochozoa and Ecdysozoa

c. Cnidaria and Bilateria

d. Deuterostomia and Bilateria

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In Figure 33.7, assume that the two medusae shown at step 4 were produced by one polyp colony. Review Concept 12.1 and Concept 13.3, and then use your understanding of mitosis and meiosis to select which of the following is true.

a. Both the medusae and the gametes are genetically identical.

b. Neither the medusae nor the gametes are genetically identical.

c. The medusae are not genetically identical but the gametes are genetically identical.

d. The medusae are genetically identical but the gametes differ genetically.