3. Class Reptilia: Reptiles Ex: Lizards, Snakes, Turtles & Crocodiles

4. Modern reptiles share 7 key characteristics… Strong, bony skeleton Ectothermic metabolism Dry, scaly skin Amniotic egg Respiration through lungs Partially divided heart Internal fertilization

5. Except for snakes, reptiles have Strong bony skeletons with Two pairs of limbs. Their legs are positioned more under The body than amphibians which Support more weight and allow Them to move about faster. They also have toes with claws.

7. Reptiles’ ectothermic metabolism Is too slow to generate enough Heat to warm their bodies, so They must absorb it from The environment.

9. Reptiles have evolved a practically Water tight skin of scales. The scales are flexible and overlap. This has allowed reptiles to leave The water and live on land.

11. Since reptiles live on dry land, they Cannot have the same eggs as Fish and amphibians. Reptiles developed a water tight egg That has its own supply of Food and water

12. All land animals have developed An efficient set of lungs. Reptiles, and future animals, Have lungs with thousands of Alveoli on the inner surface. They also have a strong set of Muscles to draw more air in And out of the lungs.

13. Lungs

14. Reptiles have a partially divided Heart that separates oxygen Rich blood and oxygen poor blood.

15. Unlike fish and amphibians, reptile Eggs are fertilized internally. This helps to protect the gametes From drying out on land. Most reptiles are oviparous, they Lay eggs from which the Young hatch.

16. A few are ovoviparous, which means That the eggs are kept inside The female until they hatch.

17. There are 4 classes of reptiles. In lizards and snakes, the lower Jaw is only loosely attached, so they Can eat things much larger than The size of their mouth. Lizards, Snakes, Crocs, & Turtles

19. Common lizards include iguanas, chameleons, and horned lizards. Most are carnivores! Most are smaller than your foot, but A komodo dragon can get to be 10 feet and weigh 500 pounds!

21. Snakes probably evolved from Lizards during the Cretaceous period. The skeleton of snakes has no Remnants of a pelvic girdle.

22. Some snakes strangle their Prey and others have poisonous venom. There are 4 types of poisonous snakes, Only one lives in this area, The water moccasin.

24. Turtles and tortoises are unique Because of their shell. They evolved about 200 Million years ago. The carapace is the top part of the Shell and the plastron is the bottom.

26. Crocodiles and alligators belong To the class crocodilian. Crocodiles have a longer thinner Snout than alligators do. American alligators can be 18 feet Long, but Nile Crocodiles can get 20 feet and weigh 1600 pounds! They are the only reptiles to care For their young.

28. Class Aves: The Birds

29. Ex. Woody Woodpecker, Roadrunner & Archaeopteryx.

30. All birds share the same 6 characteristics… Forelimbs modified into wings Body covered in feathers Lightweight bones Endothermic metabolism Super-efficient respiratory system Heart is completely divided

31. Feathers = thought to have evolved from scales

32. -like reptiles they molt -colored for camouflage or mating

33. Types

34. a. contour- cover body and give shape

36. b. flight- contours on wings and tail -Provide lift for flight

37. c. down- soft, fluffy and provide insulation

38. Preening= -preen gland

39. Strong, lightweight skeleton -thin and hollow -may be fused (keel and collarbones)

40. Endothermic metabolism -heat through metabolism -104° F to 108° F due to energy required of flight

41. Birds have a completely divided Heart, just like you.

42. Highly efficient lungs -flight demands a lot of energy -one way air flow

43. Specialized beak -no teeth or jaw -gizzard takes over role of teeth -specialized to diet

44. Pg. 800

45. Specialized foot -specialized for lifestyle