7. A biologist discovers a sister taxon of Platyhelminthes. The new taxon likely has all of the following features except a) coelom b) true organs c) triploblasty d) eye spots e) bilateral symmetry 8. Which of the following taxonomic groups lacks parasitic organisms? a) Ecdysozoa b) Nematoda c) Turbellaria d) Cestodes e) Trematoda For each of the following, select (A) True or (B) False. 9. More than 50% of extant (currently living) animals are arthropods. 10. Segmentation is a synapomorphy of Porifera. 11. According to recent molecular evidence presented in lecture, Ctenophora is conclusively the most ancestral group of organisms on the animal phylogeny. 12. On the traditional phylogeny based on morphological data, Nematoda is the most ancestral bilaterian Phylum. 13. Pseudocoelomates lack a coelom. 14. "True jelly fish" belong to the Class Scyphozoa. 15. Closed circulatory system is a synapomorphy of Mollusca. 16. Scolex is a unique and distinguishing synapomorphy of Rotifers. 17. A key distinguishing synapomorphy of Bivalvia is adductor muscles. 18. Planarians are pseudocoelomates. 19. A defining synapomorphy of Cnidaria is choanocytes. 20. Corals provide zooxanthellae with carbon dioxide and nitrogen..

1. 7. A biologist discovers a sister taxon of Platyhelminthes. The new taxon likely has all of the
following features except a) coelom b) true organs c) triploblasty d) eye spots e) bilateral
symmetry 8. Which of the following taxonomic groups lacks parasitic organisms? a) Ecdysozoa b)
Nematoda c) Turbellaria d) Cestodes e) Trematoda For each of the following, select (A) True or
(B) False. 9. More than 50% of extant (currently living) animals are arthropods. 10. Segmentation
is a synapomorphy of Porifera. 11. According to recent molecular evidence presented in lecture,
Ctenophora is conclusively the most ancestral group of organisms on the animal phylogeny. 12.
On the traditional phylogeny based on morphological data, Nematoda is the most ancestral
bilaterian Phylum. 13. Pseudocoelomates lack a coelom. 14. "True jelly fish" belong to the Class
Scyphozoa. 15. Closed circulatory system is a synapomorphy of Mollusca. 16. Scolex is a unique
and distinguishing synapomorphy of Rotifers. 17. A key distinguishing synapomorphy of Bivalvia is
adductor muscles. 18. Planarians are pseudocoelomates. 19. A defining synapomorphy of
Cnidaria is choanocytes. 20. Corals provide zooxanthellae with carbon dioxide and nitrogen.