Why Are Developmental Biologists So Interested in Studying Echinoderm Embryos

question 22

Multiple Choice

Why are developmental biologists so interested in studying echinoderm embryos?

• A) Echinoderms are primitive chordates.
• B) Echinoderms are the closest living relatives of chordates.
• C) Echinoderms are the only animals with three embryonic germ layers.
• D) Echinoderms, unlike most invertebrates, retain their notochords as adults.
• E) Echinoderms, like chordates, are protostomes.

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