Amphibian & Reptile Notes Chapter 30 & 31

Amphibians  Examples: Frogs, toads, salamanders  Habitat: Land & Fresh water

Amphibians  Characteristics  The first land vertebrates  Most have legs  Most have lungs for gas exchange  Gas exchange also across the skin (diffusion)  Double-loop circulatory system  Most frogs & toads go through external fertilization  Must reproduce in water/moist environments  Most salamanders go through internal fertilization

Section 33-3 Double-Loop Circulatory SystemSingle-Loop Circulatory System FISHESMOST REPTILESCROCODILIANS, BIRDS, AND MAMMALS

Reptiles  Examples: Turtle, lizard, snake, crocodile, dinosaur  Habitat: Aquatic and terrestrial environments

Reptiles  Characteristics  Dry skin covered with tough scales  to prevent water loss  First organisms to have an amniotic egg  Excrete waste as uric acid  “Cold blooded”  ectothermic, environment controls body temperature  Group includes dinosaurs

Reptiles  Characteristics  Most have legs (exception: snakes)  Heart with partially divided ventricle  Four living orders of reptiles: Squamata (lizard & snake), Testudines (turtles), Crocodylia (crocodiles & alligators), and Rhynchocephalia (tuataras “ancient lizards)