Question

multiple choice question
protostomes that have bilateral symmetry and three embryonic germ layers, but that do not possess a coelom or pseudocoelom, are called

o cnidarians.
o echinoderms.
o flatworms.
o nematodes.

Explanation:

• Cnidarians have radial symmetry and two germ layers.
• Echinoderms are deuterostomes.
• Flatworms (Platyhelminthes) are protostomes with bilateral symmetry, three germ layers, and no coelom or pseudocoelom.
• Nematodes have a pseudocoelom.

Answer:

flatworms.