The Circulatory System of Enteropneusts Sends Blood Anteriorly into a Series

Q42: The echinoderms and hemichordates are<br>A)asymmetrical.<br>B)diploblastic.<br>C)deuterostomes.<br>D)ecdysozoans.<br>E)lophotrochozoans.

Q43: Nutritionally,pterobranchs are<br>A)filter feeders.<br>B)parasitic.<br>C)mutualistic.<br>D)commensalists<br>E)predators.

Q44: Acorn worms belong to the class<br>A)Ascidacea.<br>B)Concentricycloidea.<br>C)Pterobranchia.<br>D)Enteropneusta.<br>E)Thaliacea.

Q45: Exchange of respiratory gases in enteropneusts is

Q46: Enteropneusta are wormlike as adults and pterobranchia

Q48: Which of the following echinoderms may contain

Q49: Enteropneusta and Pterobranchia are classes of animals

Q50: When feeding on a bivalve,a sea star

Q51: In sea stars,thin folds of the body

Q52: The major secretory and absorptive structures of