Enterocoelomates are radial.

Enterocoelomates are radial.

• A. True
• B. False
• C. Both
• D. Not known

Answer: (B)

Coelom formation is what this item tests. Enterocoelomates are deuterostomes in which the coelom forms by enterocoely—outpocketings of the archenteron that pinch off to become coelomic sacs. Radial symmetry, by contrast, is a body-plan trait describing how body parts arrange around an axis, and it is not tied to the method of coelom formation. In this group, adult echinoderms show radial symmetry, but chordates and many deuterostomes are bilaterally symmetric as adults (and even echinoderms are bilateral in the larval stage). Therefore, being an enterocoelomate does not guarantee radial symmetry, making this statement false.

Coelom formation is what this item tests. Enterocoelomates are deuterostomes in which the coelom forms by enterocoely—outpocketings of the archenteron that pinch off to become coelomic sacs. Radial symmetry, by contrast, is a body-plan trait describing how body parts arrange around an axis, and it is not tied to the method of coelom formation. In this group, adult echinoderms show radial symmetry, but chordates and many deuterostomes are bilaterally symmetric as adults (and even echinoderms are bilateral in the larval stage). Therefore, being an enterocoelomate does not guarantee radial symmetry, making this statement false.