1. Reptiles

2. What is a Reptile? •Fully terrestrial •Dry, scale-covered skin
•Ectothermic
•Most have 3 chambered hearts (except alligators and crocodiles)
•Internal fertilization
•Amniotic eggs typically laid on land

3. Reptile Circulation
Reptiles have a partially
divided ventricle

4. Form & Function in Reptiles
•Well developed lungs
•Double-loop circulatory system
•Water-conserving excretory system
•uric acid – terrestrial waste
•ammonia – aquatic waste (crocs & gators!)
•Strong limbs
•Internal fertilization
•Amniotic eggs contributed to success on land

5. Ectothermic – have the ability to control their body
temperature by basking in the sun and moving to shade during the day.
Jacobson’s Organ – sensory organ located in the roof of the mouth used for detecting chemicals when reptiles flick their tongues.

6. Reproduction in Snakes
Oviparous birth
pythons & cobras (egg hatches outside mother)
Viviparous
copperheads, boa constrictors,
rattlesnakes, & garter snakes (live birth)
Ovoviviparous
Water snakes (eggs hatch inside mother &
young born live)

7. Venomous vs. Nonvenomous
Characteristic
Pit Viper
Non-poisonous
Triangle-shaped
head
Oval head
Flat head
Rounded head
Elliptical pupils /
Pits
Round pupils / no
pits

8. Amniotic Egg
Amnion – fluid filled sac that cushions the developing embryo
Chorion – regulates transport of oxygen to embryo and carbon dioxide to the outside of egg.
Yolk sac – nutrient rich food supply for embryo
Allantois – stores the waste produced by embryo

9. Orders of Reptiles Squamata (lizards & snakes)
Testudines (turtles & tortoises

10. Crocodilia (crocodiles & alligators)
Endothermic & 4-chambered heart
Sphenodonta (tuatara)