1. KEY CONCEPT All vertebrates share common characteristics.

2. tail hollow nerve cord notochord pharyngeal slits The phylum Chordata contains all vertebrates and some invertebrates. Chordates share four features at some stage of development. notochord hollow nerve cord pharyngeal slits tail

4. All vertebrates share common features. An endoskeleton allows vertebrates to grow to large sizes. internal made of bone or cartilage

7. bones

8. gill arches (in fish and some amphibians)vertebrae bones

10. Agnatha are jawless fish, such as hagfish.

11. Cartilaginous fish (Chondrichthyes) include the sharks and rays

12. Bony fish (Osteichthyes) obviously have bones.

13. Amphibians are characterized by the presence of four limbs and water permeable skin.

14. Reptiles, birds, and mammals are characterized by the presence of an amnion and water-tight skin.

15. Birds are characterized by the presence of feathers.

19. water flow Fish are vertebrates with gills and paired fins. Fish use specialized organs called gills to breathe underwater. sheets of thick, frilly tissue filled with capillaries take in dissolved oxygen from water, release carbon dioxide

21. keep fish stable

22. redirect water around fish as it swims

25. Holocephali include ratfish, a small group of deep-sea fish.

27. sensory system

29. operculum protects a bony fish’s gills

35. can breathe air and survive out of water for several hours at a time

38. coelacanths

40. Amphibians were the first animals with four limbs. Tetrapods are vertebrates that have four limbs. The fossilized remains of Tiktaalik roseae indicate it was a transitional species between fish and tetrapods.

42. large shoulder and hip bones

43. mobile, muscular tongue

44. middle ear

47. During metamorphosis, tadpoles develop into their adult form.

50. There are over 3000 species of frogs.

53. Amnion Protectsand surroundsthe embryo Amniotes can retain moisture. An amniote develops inside a thin, tough, membranous sac as an embryo or fetus.

55. keratin forms a hydrophobic layer

58. reptiles such as garter snakes retain their eggs

60. lines the uterine wall and partially envelops the fetus

61. carries nutrients from mother to embryo and removes wastes