By Sarah KahanicGrade: 6-8

Subject: Life Science

Amphibians!

Lay Eggs in WaterEggs don’t have shellsBorn with gillsCold-bloodedMoist SkinDevelop lungs and

legs Live on land at maturity

What is an Amphibian?

All amphibians start life as an egg in a ball of jelly. The eggs are laid in water. The egg hatches and the young amphibian breaks out of the jelly. We call the young of a frog or toad a tadpole. The young amphibian has gills to breathe underwater and a tail with a fin so it can swim. When it gets bigger it starts to grow legs. When it is full grown it changes quickly to its adult body shape. It loses its gills and grows lungs to breathe air. It loses its tail fin and its legs grow much larger. Then it leaves the water to live on land. It looks like an adult now, only much smaller.It takes a couple of years for an amphibian to grow to its adult size. In spring the adult will return to the pond, lake or stream where it was born to look for a mate. Then the females lay eggs to start the cycle over again.(Nature North)

Life Cycle of an Amphibian

Life Cycle of a Typical Amphibian

Life Cycle Video

FrogsToadsSalamanders Newts

Fours DifferentTypes of Amphibians

Newts and Salamanders are both belong to the group “Urodela” which are amphibians with four legs and a tail at maturity. These amphibians resemble lizards

Newts are a subset of the Salamander speciesAll newts are salamanders,

but not all salamandersare newts

Newts and Salamanders

SalamandersNocturnal Spends most of life

in or by water

PoisonousBrightly ColoredActive during the

dayMore complex life

cycle (spends days away from water)

Differences between Newts and Salamanders

Newts

UrodelaAnuraAnapsid Parareptilia

What is the name for the group of amphibians the Newt belongs to?

Incorrect

Please select the button and reread the section on Newts before continuing

Correct!

Both Frogs and Toads belong to the group “Anura” that lacks tails and have long hind legs well-adapted for jumping and swimming

Frogs and Toads

Frogtwo bulging eyes strong, long, webbed

hind feet that are adapted for leaping and swimming

smooth or slimy skin (generally, frogs tend to like moister environments)

Frogs tend to lay eggs in clusters.

stubby bodies with short hind legs (for walking instead of hopping)

warty and dry skin (usually preferring dryer climates)

paratoid (or poison) glands behind the eyes

The chest cartilage of toads is different also.

Toads tend to lay eggs in long chains.

Differences Between Frogs and Toads

Toads

Select which picture is the toad

Incorrect

Please select the button and reread the differences between toads and frogs before continuing

Correct!

Congratulations! You have finished this mini lesson.

This mini lesson was created by Sarah Kahanic for EDU 103

For more information Email: srhkhnc@dordt.edu

Bio Page

Life Science by Mc Dougal Littell (2006)http://www.scienceclarified.com/Al-As/

Amphibians.htmlhttp://allaboutfrogs.org/weird/general/

frogtoad.htmlhttp://www.flickr.com/groups/salamanders/

discuss/72157594451142303/http://www.naturenorth.com/1np/Species/

amphibian/Lifcyc/Flfcyc.html

References and Resources