ch 32 pt 2 – Flashcards

31) According to the evidence collected so far, the animal kingdom is A) monophyletic. B) paraphyletic. C) polyphyletic. D) euphyletic. E) multiphyletic.

32) If a multicellular animal lacks true tissues, then it can properly be included among the A) eumetazoans. B) metazoans. C) choanoflagellates. D) lophotrochozoans. E) bilateria.

33) Which of the following statements concerning animal taxonomy is (are) true? 1. Animals are more closely related to plants than to fungi. 2. All animal clades based on body plan have been found to be incorrect. 3. Kingdom Animalia is monophyletic. 4. Only animals reproduce by sexual means. 5. Animals are thought to have evolved from flagellated protists similar to modern choanoflagellates. A) 5 only B) 1 and 3 C) 3 and 5 D) 3, 4, and 5

34) If the current molecular evidence regarding animal origins is well-substantiated in the future, then what will be true of any contrary evidence regarding the origin of animals derived from the fossil record? A) The contrary fossil evidence will be seen as a hoax. B) The fossil evidence will be understood to have been incorrect because it is incomplete. C) The fossil record will henceforth be ignored. D) Phylogenies involving even the smallest bit of fossil evidence will need to be discarded. E) Only phylogenies based solely on fossil evidence will need to be discarded.

35) What is true of the clade Ecdysozoa? A) It includes all animals that molt at some time during their lives. B) It includes all animals that undergo metamorphosis at some time during their lives. C) It includes all animals that have body cavities known as pseudocoeloms. D) It includes all animals with genetic similarities that are shared with no other animals. E) It includes all animals in the former clade Protostomia that truly do have protostome development.

36) Which distinction is given more emphasis by the morphological phylogeny than by the molecular phylogeny? A) metazoan and eumetazoan B) radial and bilateral C) true coelom and pseudocoelom D) protostome and deuterostome E) molting and lack of molting

37) The last common ancestor of all bilaterians is thought to have had four Hox genes. Most extant cnidarians have two Hox genes, except Nematostella (of β-catenin fame), which has three Hox genes. On the basis of these observations, some have proposed that the ancestral cnidarians were originally bilateral and, in stages, lost Hox genes from their genomes. If true, this would mean that A) Radiata should be a true clade. B) the radial symmetry of extant cnidarians is secondarily derived, rather than being an ancestral trait. C) Hox genes play little actual role in coding for an animal's "body plan." D) Cnidaria may someday replace Acoela as the basal bilaterians. E) Two of the responses above are correct.

38) Which of these, if true, would support the claim that the ancestral cnidarians had bilateral symmetry? 1. Cnidarian larvae possess anterior-posterior, left-right, and dorsal-ventral aspects. 2. Cnidarians have fewer Hox genes than bilaterians. 3. All extant cnidarians, including Nematostella, are diploblastic. 4. β-catenin turns out to be essential for gastrulation in all animals in which it occurs. 5. All cnidarians are acoelomate. A) 1 only B) 1 and 4 C) 2 and 3 D) 2 and 4 E) 4 and 5

39) Some researchers claim that sponge genomes have homeotic genes, but no Hox genes. If true, this finding would A) strengthen sponges' evolutionary ties to the Eumetazoa. B) mean that sponges must no longer be classified as animals. C) confirm the identity of sponges as "basal animals." D) mean that extinct sponges must have been the last common ancestor of animals and fungi. E) require sponges to be reclassified as choanoflagellates.

70) Among the characteristics unique to animals is A) gastrulation. B) multicellularity. C) sexual reproduction. D) flagellated sperm. E) heterotrophic nutrition.

71) The distinction between sponges and other animal phyla is based mainly on the absence versus the presence of A) a body cavity. B) a complete digestive tract. C) a circulatory system. D) true tissues. E) mesoderm.

72) Acoelomates are characterized by A) the absence of a brain. B) the absence of mesoderm. C) deuterostome development. D) a coelom that is not completely lined with mesoderm. E) a solid body without a cavity surrounding internal organs.

73) Which of the following was probably the least important factor in bringing about the Cambrian explosion? A) the emergence of predator-prey relationships among animals B) the accumulation of diverse adaptations, such as shells and different modes of locomotion C) the movement of animals onto land D) the origin of Hox genes and other genetic changes affecting the regulation of developmental genes E) the accumulation of sufficient atmospheric oxygen to support the more active metabolism of mobile animals

http://www.easynotecards.com/uploads/375/0/_39367d51_13ab9201884__8000_00000092.jpg 74) Which of the following is a point of conflict between the phylogenetic analyses presented in these two figures? A) the monophyly of the animal kingdom B) the relationship of taxa of segmented animals to taxa of nonsegmented animals C) that sponges are basal animals D) that chordates are deuterostomes E) the monophyly of the bilaterians