Chapter 34 Vertebrates Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

An adult tunicate (sea squirt) is a sessile filter-feeder that resembles a sponge more than a fish. Why is this particular group thought to be more closely related to vertebrates than are the other invertebrate chordates? They share the same 13 chordate Hox genes. They have a free-swimming larval stage. They have pharyngeal slits unlike the other invertebrate chordates. They have a notochord unlike the other invertebrate chordates. They are larger in size than other invertebrate chordates. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

One feature unique to craniate chordates (having a head) is the neural crest. Which best describes the fate of neural crest cells? They become the brain of the animal. They become the brain and spinal cord. They become some teeth and bones of the skull. They become an extensive muscular system. They become the chambered heart. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Why are humans considered members of the chordates when we have no notochord, pharyngeal slits, or muscular tail? Our mammalian ancestors show some of these traits. Other similar traits appear in humans. Our nerve cord has replaced the notochord. These traits are only found in invertebrate chordates. These chordate traits appear in human embryos. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following traits is shared by all vertebrates, at least in some developmental stages, except the lampreys? notochord vertebrae cartilaginous skeleton cranium (head) mouth with jaws Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Members of the bony-fish clade (Osteichthys) are very diverse Members of the bony-fish clade (Osteichthys) are very diverse. Of the following pairs, which one does not represent two classification subgroups within the Osteichthys clade? ray-finned and lobe-fins lungfishes and coelocanths lungfishes and tetrapods freshwater and salt water Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

When early systematists distinguished Chondrichthyes (cartilaginous fish) from Osteichthyes (bony fish), it was not clear exactly when bony skeletons first appeared in the vertebrates. Which of these suggests that a reduction of bone in Chondrichthyes is a derived condition that emerged after the origin of bony fish skeletons? All fish except Agnatha have jaws. Chondrichthyes and Osteichthyes have paired fins and lateral lines. Traces of bone tissue are found in living and fossil Chondrichthyes. The cartilage skeleton of Chondrichthyes is impregnated with calcium. Chondrichthyes do not have swim bladders like those of Osteichthyes. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Most amphibians undergo metamorphosis from an aquatic larva to a more terrestrial adult. Which of the following is not part of that metamorphosis? finned tail  legs lateral line  eardrum gills  lungs aquatic food  terrestrial food smooth skin  scaly skin Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of the following is not a new adaptation of birds that supports flight? feathers on wings and tail four-chambered heart and efficient lung tubes protein beak in place of mineralized teeth amniotic egg hollow bones Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

Which of these correctly describes phylogenetic relationships among birds, mammals, and reptiles? Birds share the closest common ancestor with dinosaurs. Reptiles and birds, but not mammals, are amniotes. Mammals evolved from therapsid reptiles after the fall of the dinosaurs. Birds and mammals are more closely related to each other than either group is to crocodilian reptiles. Among living species in the group we call reptiles, turtles and snakes are most closely related to each other. Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.

All of the following except which one is a correct match for the name of a taxonomic group containing humans and the generalized distinguishing characteristics of that taxon? genus Homo: short jaw, large brain hominin (“hominid”) family of genera: upright posture, bipedal locomotion order Primates: grasping thumbs, forward-facing eyes class Mammalia: placenta joining fetus and mother, development entirely within uterus species sapiens: slender body, lack heavy brow ridge, cave paintings Copyright © 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings.