Eggs are usually laid in water or in a moist environment Eggs are fertilized externally Eggs lack shell CLASSIFICATION Phylum Amphibia Biologists identified 2,375 different species of amphibians Biologists divide them into four orders Anura (without tail) Urodela (visible tail) Apoda (without legs) Trachystoma (rough mouth) Anura (frogs and toads) Live in environments such as deserts, mountains, ponds and puddles Most live in or near water and some live in trees Frogs Smooth moist skin Short broad bodies Long hind legs -&gt; excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water to reproduce Most have external fertilization Fertilized eggs hatch into swimming larvae called tadpoles Urodela (salamanders) Have elongated bodies and long tails Smooth moist skin Less able to survive &quot;dry&quot; habitats Reproduction Eggs usually laid in water Some in damp terrestrial environments Internal fertilization (females pick up sperm from males) Hatch into swimming larval forms in aquatic salamanders Hatch into mini-adult salamanders in terrestrial forms Diagram - Salamander- external form Diagram - Salamander- internal structure Diagram - Salamander- skeleton Diagram - Salamander- circulatory system Apoda and Trachystoma (Caecilians) Tropical burrowing amphibians Have minute forelimbs and lack hindlimbs Average is 30 cm;
(Most; live; L:in or near water) (excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water; have; ) Context(excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671))):(Eggs; are laid; in water or in a moist environment Eggs; T:externally Eggs lack shell CLASSIFICATION Phylum Amphibia Biologists identified 2,375 different species of amphibians Biologists; T:usually) Context(excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671))):(excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water; have to reproduce; Most) Context(excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671))):(Long; hind; legs -&gt) Context(excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671))):(habitats Reproduction Eggs; laid; in water; T:usually) Context(excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have habitats Reproduction Eggs laid,List([531, 907))):(external fertilization; Fertilized; eggs hatch) (Smooth moist skin; to survive; ) (Eggs; are fertilized; ) (some; live; L:in trees Frogs Smooth moist skin Short broad bodies) (females; pick up; sperm; from males; T:larval forms in aquatic salamanders; T:Hatch) (swimming larvae; called; tadpoles Urodela) (Tropical burrowing amphibians; Have; minute forelimbs and lack hindlimbs) (Toads Well; adapted; to dry environments; Dry bumpy skin Stocky bodies Short legs) (frogs and toads; Live; L:in environments such as deserts, mountains, ponds and puddles)
excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671)) excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671)) excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671)) excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have,List([531, 671)) excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water have habitats Reproduction Eggs laid,List([531, 907))
Most excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water Eggs excellent jumpers Toads Well adapted to dry environments Dry bumpy skin Stocky bodies Short legs Both return to water Long habitats Reproduction Eggs external fertilization Smooth moist skin Eggs some females swimming larvae Tropical burrowing amphibians Toads Well frogs and toads
live have are laid have to reproduce hind laid Fertilized to survive are fertilized live pick up called Have adapted Live
L:in or near water
in water or in a moist environment Eggs T:externally Eggs lack shell CLASSIFICATION Phylum Amphibia Biologists identified 2,375 different species of amphibians Biologists T:usually
Most
legs -&gt
in water T:usually
eggs hatch
L:in trees Frogs Smooth moist skin Short broad bodies
sperm from males T:larval forms in aquatic salamanders T:Hatch
tadpoles Urodela
minute forelimbs and lack hindlimbs
to dry environments Dry bumpy skin Stocky bodies Short legs
L:in environments such as deserts, mountains, ponds and puddles