AMPHIBIANS

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AMPHIBIANS REPTILES ARE ADAPTED FOR LIFE ON LAND

• VERTEBRATES ADAPTED TO LIVE ON LAND.
• AMPHIBIANS HAVE MOIST SKIN LAY EGGS WITHOUT
  SHELLS.
• REPTILES HAVE DRY, SCALY SKIN LAY EGGS WITH
  SHELLS.
• BODY TEMPERATURES OF AMPHIBIANS REPTILES CHANGE
  WITH THE ENVIRONMENT.

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Vertebrates Adapted to Live on Land

• Amphibians (frog/toad/salamanders) Reptiles
  (turtle/snake/lizards/crocodiles) have adapted to
  live on land.
• Some fish can breathe air and walk short
  distances on land.
• Some amphibians have adapted to life only in
  water.

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Amphibians moist skin eggs without shells

• Most adult amphibians have 2 pairs legs (4
  limbs), lay eggs in water, get oxygen thru
  smooth, moist skin, have lungs, sense organs
  adapted for land.
• Most live in moist or damp environments
• Reproduce sexually (female lays eggs in water
  male fertilizes them in water with sperm)
  offspring develop hatch on own- yolk inside
  eggs gives nutrients soft shells so water (with
  dissolved oxygen) can pass through.

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Amphibian Life Cycle

• Young amphibian hatches as a larva (tadpoles for
  frogs toads look act like small fish-
  breathe via gills, swim with tail)
• After few weeks, tadpoles body changes (lungs
  develop, tail shrinks, legs form)
• Young frogs body changes gills stop working so
  breathes with lungs, uses tongue to capture eat
  small animals, uses legs to move around on land.
• Some amphibians stay near water (sirens,
  bullfrogs), while some just go to moist areas
  (wood frogs, toads, salamanders)

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Reptiles have dry, scaly skin lay eggs with
shells

• Most have 2 pairs legs (total 4 limbs) have
  tough, dry skin covered by scales get oxygen
  from air with lungs sensory organs adapted for
  land lay eggs (with shells) on land.
• Lungs born with lungs, filled with tiny blood
  vessels where oxygen is exchanged with carbon
  dioxide waste.
• Dry, scaly, skin covered with scales made of
  keratin (like fingernails). Thick, waterproof
  skin protects from environment predators (but
  cant exchange oxygen through skin).

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Reptile Eggs with Shells

• Reptile egg lets vertebrate animals survive in
  hot, dry environment.
• Eggs have everything embryo needs (water,
  nutrients, gas exchange).
• Reptiles reproduce sexually (sperm fertilizes
  egg, then shell forms around it-while still
  within female).
• Female finds place to lay eggs (usually nest or
  buries them).

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Amphibians Reptiles areEctotherms

• Are Ectotherms body temperature changes with
  environmental conditions can move more quickly
  when warm. Usually warm themselves in sunlight.
• Most of food is changed right into energy. Some
  (alligator tortoise) may survive long time
  without eating food.
• If too hot or too cold, body stops working well.
  (usually live where temp. doesnt change too
  much- or may hibernate slow down body processes
  in cold)
• Many live near water to cool off.

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