FrogsFrogsChange happensChange happens

FROGS ARE FROGS ARE AMPHIBIANSAMPHIBIANS

AMPHIBIAN: Living both AMPHIBIAN: Living both in water and on land in water and on land They begin life in the They begin life in the

water as an egg, grow into water as an egg, grow into tadpoles that breathe with tadpoles that breathe with gills and then grow into gills and then grow into adults that breathe air adults that breathe air (from Greek (from Greek amphibionamphibion: : amphi ‘both’ amphi ‘both’ + + bios bios ‘life’ )‘life’ )

Some types of Some types of amphibians:amphibians: Frogs and ToadsFrogs and Toads Salamanders and NewtsSalamanders and Newts

It’s a Frog’s LifeIt’s a Frog’s Life

Frogs begin life as an egg Frogs begin life as an egg

Female frogs can lay as Female frogs can lay as many as 20,000 eggs at many as 20,000 eggs at one timeone time

The eggs have to be The eggs have to be fertilized by a male frogfertilized by a male frog

Frog eggs have a Frog eggs have a protective jelly-like protective jelly-like coating that tastes bad to coating that tastes bad to predatorspredators

The egg masses are called The egg masses are called eggegg sackssacks or or frogspawnfrogspawn

Life BeginsLife Begins

It takes about 6 to 21 days for a It takes about 6 to 21 days for a frog egg to hatchfrog egg to hatch

The tadpoles wiggle inside the egg The tadpoles wiggle inside the egg until they can break freeuntil they can break free

Tadpoles emerge from the egg, Tadpoles emerge from the egg, eating the remains of their eggeating the remains of their egg

Tadpoles have a mouth, poorly Tadpoles have a mouth, poorly formed gills for breathing, and a formed gills for breathing, and a tail tail

Tadpoles eat algae and Tadpoles eat algae and camouflage is their only camouflage is their only protection. They hide in plantsprotection. They hide in plants

Metamorphosis Metamorphosis

Metamorphosis is the change in Metamorphosis is the change in the form or structure after birth or the form or structure after birth or hatchinghatching

At 6 to 9 weeks, the tadpole has At 6 to 9 weeks, the tadpole has grown tiny legs and arms and can grown tiny legs and arms and can breath air as its lungs developbreath air as its lungs develop

A tadpole grows legs first and then A tadpole grows legs first and then arms. Skin grows over their gillsarms. Skin grows over their gills

They begin to eat insects and They begin to eat insects and plantsplants

Watch this video of the process so Watch this video of the process so far: far: from egg to froglet

FrogletFroglet

At 12 weeks, the At 12 weeks, the tadpole’s body, legs, tadpole’s body, legs, and arms are bigger and arms are bigger and its tail is smaller. and its tail is smaller. The tadpole has The tadpole has become a ‘froglet’become a ‘froglet’

Froglets can live Froglets can live outside of the water, outside of the water, they breath air and they breath air and eat insectseat insects

Froglets reabsorb their Froglets reabsorb their tail to help them growtail to help them grow

FrogFrog

Once the tail is fully Once the tail is fully absorbed, the froglet absorbed, the froglet has become a frog has become a frog

Frogs eat insects and Frogs eat insects and wormsworms

Frogs stay close to the Frogs stay close to the water so the cycle can water so the cycle can begin againbegin again

Fun FactsFun Facts

The largest frog in the world, Africa’s Goliath Frog: The largest frog in the world, Africa’s Goliath Frog: http://thexodirectory.com/2007/12/goliath-frog-worlds-http://thexodirectory.com/2007/12/goliath-frog-worlds-largest-frog/ largest-frog/ The smallest frog in the world: you decide. The smallest frog in the world: you decide.

The Bornean Micro Frog:The Bornean Micro Frog:http://news.nationalgeographic.com/news/2010/08/photogalleries/100825-new-species-pea-size-frog-science-pictures/

Monte Iberia Eleuth: Monte Iberia Eleuth: http://www.wereyouwondering.com/what-is-the-smallest-frog-in-the-world/

Stumpffia pygmaea: Stumpffia pygmaea: http://amphibiaweb.org/cgi-bin/amphib_query?where-scientific_name=Stumpffia+pygmaea

Want to know more? Visit:Want to know more? Visit: http://www.amnh.org/exhibitions/frogs/frogfacts/http://www.amnh.org/exhibitions/frogs/frogfacts/

ResourcesResources

http://allaboutfrogs.org/weird/general/cycle.html Retrieved 8/6/2011

http://bogglesworldesl.com/froglifecycle.htm Retrieved 8/6/2011

http://www.learner.org/jnorth/search/FrogNotes3.html Retrieved 8/6/2011

http://www.californiaherps.com/frogs/frogs.html Retrieved 8/6/2011

http://video.nationalgeographic.com/video/http://video.nationalgeographic.com/video/player/kids/animals-pets-kids/amphibians-kids/player/kids/animals-pets-kids/amphibians-kids/frog-tadpole-kids.html Retrieved 8/6/2011frog-tadpole-kids.html Retrieved 8/6/2011

California Department of California Department of Education Content Standard; Education Content Standard;

Science Science Grade TwoGrade Two

Life SciencesLife Sciences

2. Plants and animals have predictable life 2. Plants and animals have predictable life cycles. As a basis for understanding this cycles. As a basis for understanding this concept:concept: a. a. Students know Students know that organisms reproduce that organisms reproduce

offspring of their own kind and that the offspring of their own kind and that the offspring resemble their parents and one offspring resemble their parents and one another.another.

b. b. Students know Students know the sequential stages of life the sequential stages of life cycles are different for different animals, such cycles are different for different animals, such as butterflies, frogs, and mice.as butterflies, frogs, and mice.

Expanding the LessonExpanding the Lesson

A Web Quest: A Web Quest: http://www.ourclassweb.com/webquests_frogshttp://www.ourclassweb.com/webquests_frogs_introduction.htm_introduction.htm

Ribbit! Ribbit! A thematic unit on frogs by Ribbit! Ribbit! A thematic unit on frogs by Christine Gorman: Christine Gorman: http://www.everythingesl.net/lessons/http://www.everythingesl.net/lessons/Christine_Gorman.phpChristine_Gorman.php