1. Chapter 3
Section 4

2. Drying Out Reptile: Types of Reptiles:
Ectothermic vertebrate that has lungs and scaly skin
Types of Reptiles:
Snakes, lizards, turtles, and alligators

3. Reptiles Background Can spend their entire life on dry land
1st vertebrates that are well adapted to life on land
Dominant land species for 160 million years
7,000 kinds of reptiles are alive today

4. Reptiles Adaptations to life on land
Eggs
Skin
Kidneys
Adaptations help them conserve water

5. Egg with a Shell What type of fertilization do reptiles use?
Internal fertilization
Fertilized eggs are covered with a membrane and a shell
The membrane and shell protect the embryo and prevent it from drying out

6. Egg with a Shell Amniotic Egg Information Soft and leathery
Tiny holes let oxygen in and carbon dioxide out
Eggs can be laid on land
1 membrane holds the liquid that surrounds the embryo – keeps it from being crushed and keeps it moist
2nd membrane holds the yolk or food
3rd membrane holds the wastes

7. Egg with a Shell

8. Skin and Kidneys What type of skin did amphibians have?
Thin and moist
How is a reptiles skin different?
It is dry, tough, and covered with scales
What is the function of scales?
Protection
Conserve water in their body

9. Skin and Kidneys What is the other organ that helps conserve water?
Kidneys filter out the waste from the blood
The waste from the blood is excreted in the urine
Concentrate their urine so much that they barely lose any water

10. Obtaining Oxygen Have a heart with 2 atria and 1 ventricle
Breathe entirely with lungs
2 loops for their blood to circulate
1st blood travels from the heart to the lungs back to the heart
Becomes oxygenated
2nd loop travels from the heart to the tissues
Oxygen moves out of the blood and into the tissues
Then the blood returns to the heart

12. Lizards Live in warm areas Have skin with overlapping scales
Shed their skin replacing worn scales with a new coat

13. Lizards Eating Habits A Lizard’s Body A few lizards are herbivores
Most are carnivores
Eat frogs, ground-dwelling birds, and insects
A Lizard’s Body
4 legs and claws with toes
Long tails
Slender bodies
Moveable eyelids
External ears

14. Snakes Snake bodies: Similar to lizards but streamlined No legs
No eyelids
No external ears
Most have only 1 lung

15. Snakes
Movement:
Contract bands of muscles that are connected to their ribs and backbones
Alternating contractions creates a slithering side-to-side motion

16. Snakes Eating: All snakes are carnivores
They can spread their jawbones wide apart
A snake’s skull can move to let the snake swallow an animal much larger in diameter than itself

17. Snakes

18. Snakes Eating Cont’d: Sharp-tailed snakes of W. North America
Hook their slippery prey
West Indian Boas
Snatch their prey out of the air
Rattlesnakes and copperheads
Venom glands

19. Turtles Reptile covered by a protective shell
Made from its ribs and backbone
Shell sizes and strengths vary
Examples on 108 in the reading
There are turtles that are carnivores while some are herbivores

20. Alligators and Crocodiles
Largest living reptiles
Spend most of their day resting in the sun or lying in the water
How do you tell an alligator from a crocodile?
Alligators have a broad, rounded snout with only a few visible teeth
Crocodiles have a pointed snout and you can see most of their teeth

21. Alligators and Crocodiles

22. Alligators and Crocodiles
Carnivores that hunt at night
Strong, muscular tails to swim rapidly
Large, sharp teeth
Extremely strong jaw muscles
Usually do not attack humans

23. Alligators and Crocodiles
Care for their eggs and newly hatched young
After birth the mother scoops them into her mouth and carries them to a safer location
Typically females stay with the young for up to a year

24. Dinosaurs
million years ago reptiles were the major form of vertebrate
May have been endothermic
Have been extinct for 65 million years
Due to climate
Huge meteorite