Frog metamorphosis

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Frog Metamorphosis The Life Cycle of Frogs

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This was a report I made in my course. I hope it helps

Transcript of Frog metamorphosis

Page 1: Frog metamorphosis

Frog Metamorphosis

The Life Cycle of Frogs

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What is Metamorphosis?

A typically marked or more or less abrupt developmental change in the form or structure of an animal occuring subsequent to birth or hatching

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How does it Work?

Metamorphosis in amphibians is regulated by thyroxin and prolactin

Development is subject to many adaptations due to specific ecological circumstances

They also make use of the lateral line organ

Redundant organs are reabsorbed via apoptosis after metamorphosis

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A Frog’s Life Cycle

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The Egg

The egg begins as a single cell

It becomes surrounded by a jellylike covering, which protects the egg

The female may or may not stay with the eggs to take care of the young after she had laid them

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The Embyo

The mass of cells in the egg come to form an embryo

Organs and gills begin to form, and the embryo lives off the internal yolk

This supplies it with nutrients for 21 days

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The Tadpole

After its 21 day development period, the embryo leaves its jelly shell, and attaches itself to a weed in the water

It has external gills like a fish to absorb oxygen and feeds on algae

It is extremely vulnerable, and must rely on its camouflage to protect it

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The Changing Tadpole

About five weeks, the tadpole begins to change

It starts to grow hind legs, which are soon followed with forelegs

Lungs begin to develop, preparing the frog for its life on land

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The Froglet

Over time, the tadpole becomes even more froglike

Its mouth widens, it loses its horny jaws, gills are lost

The tail becomes much smaller, and the legs grow

The lungs are almost functioning at this point

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The Frog

Eleven weeks after the egg was laid, a fully developed frog with lungs, legs, and no tail emerges from the water

Eventually, it finds a mate

The female lays the eggs, the male fertilizes them, and the whole process begins again