Web Results


Amniotic eggs are the evolutionary separation between amphibians and reptiles. Amphibians lay eggs that must remain moist. Lacking a protected fluid-filled cavity requires the non-amniotic eggs of amphibians to remain in water. With the development of the amniotic egg, reptiles were able to lay their eggs on land.


The eggs could also "breathe" and cope with wastes, allowing the eggs and the amniotes themselves to evolve into larger forms. The amniotic egg represents a critical divergence within the vertebrates, one enabling amniotes to reproduce on dry land—free of the need to return to water for reproduction as required of the amphibians.


Amniote Egg The amniotic egg was an evolutionary invention that allowed the first reptiles to colonize dry land more than 300 million years ago. Fishes and amphibians must lay their eggs in water and therefore cannot live far from water. But thanks to the amniotic egg, reptiles can lay their eggs nearly anywhere on dry land.


Best Answer: The reason we consider amniotic eggs so important is that we're descended from them (the same reason we tend to think the evolution of internal skeletons is more important than the evolution of exoskeletons or shells, even though exoskeletons and shells are far more widespread). Amniotic eggs did make it much easier for animals to reproduce on land away from bodies of water.


An amniotic egg is an egg which contains an amnios, a fluid filled membrane that surrounds the embryo to protect it. All reptiles, birds, and mammals produce amniotic eggs during reproduction.


23) Why is the amniotic egg considered an important evolutionary breakthrough? a. It has a shell that increases gas exchange. b. It allows incubation of eggs in a terrestrial environment. c. It prolongs embryonic development. d. It provides insulation to conserve heat. e. It permits internal fertilization to be replaced by external fertilization.


The last structure of the amniotic egg is the egg shell, which allows gases to pass through, but keeps fluids from passing into or out of the egg. Examples of Amniotic Eggs. Now that you know what ...


a. Amniotic egg is i. An egg which contains a membrane that protects the embryo ii. extramembrane sac contains yolk sac, amnion, chorion and allantois b. Embryos are more protected c. Embryo has better chance at survival - is encased with food source from mother


Reptiles: scales and the amniotic egg. ... Amniotic egg appears very early in reptilian evolution. Egg has several special extra-embryonic membranes, which allow it to develop on land independent of water. Just as significant as evolution of jaws to the evolution of vertebrates.


The placenta is a "modified egg". In the placental mammals the membranes found in the egg have been modified somewhat. The embryo is still surrounded by an amnion filled with amniotic fluid; because it is next to and surrounds the embryo, doctors will sometimes examine the fluid to determine the health of the unborn child.