Chapter 19 Vocabulary

123456789101112131415161718192021222324
Across
  1. 1. a gas-filled internal sac that helps bony fishes maintain buoyancy (2 words)
  2. 4. organism that does not produce enough heat to effect body temperature
  3. 6. mammal whose young completes development in the uterus
  4. 9. organ that provides nutrients and oxygen to the embryo
  5. 12. a system of sensory organs along each side of a fish's body that is sensitive to changes in water pressure (2 words)
  6. 13. a vertebrate with two pairs of limbs
  7. 15. the human branch of the evolutionary tree
  8. 16. a chordate animal with a backbone
  9. 17. cartilaginous fish
  10. 20. clade of amniotes that possess mammary glands and hair
  11. 22. member of a clade of tetrapods that have an amniotic egg
  12. 24. bony fish with fins supported by thin, flexible skeletal rays
Down
  1. 2. clade of tetrapods that includes frogs, toads
  2. 3. an arrangement of the fingers where the thumb can touch the fingertips of all four fingers
  3. 5. an egg-laying mammal
  4. 7. clade of tetrapods that include snakes, lizards
  5. 8. the study of human origins and evolution
  6. 10. placental mammal whose young complete their embryonic development within the uterus
  7. 11. a chordate with a head
  8. 14. a protective flap on each side of a fish's head that covers the gills
  9. 18. a shelled egg in which an embryo develops within a fluid-filled amniotic sac and nourished by yolk (2 words)
  10. 19. a pouched mammal, such as a kangaroo, opossum, or koala
  11. 21. fish with strong muscular fins supported by bones
  12. 23. clade of reptiles that have feathers and adaptations for flight