EVERYDAY SCIENCE

Detailed explanation-1: -The development of the amniotic egg was an important adaptation because it allowed vertebrates to reproduce on land. Without the self-contained source of energy and water, an egg needed to develop in water or else the embryo would dry out.

Detailed explanation-2: -The amnion is a fluid-filled sac where the embryo develops. The fluid in the sac keeps the embryo moist. Birds, reptiles, and mammals have amniotic eggs. Because amphibian eggs don’t have an amnion, the eggs would dry out if they were laid on the land, so amphibians lay their eggs in water.

Detailed explanation-3: -In amniotes, the shell of the egg provides protection for the developing embryo and allows water retention while still being permeable to gas exchange. Amniotic eggs contain albumin, which provides the embryo with water and protein, and an egg yolk that supplies the embryo with energy.

Detailed explanation-4: -It has a shell to help prevent drying, and a series of membranes that surround the developing chick. This kind of egg is unique to the amniotes, a group that includes turtles, lizards, birds, dinosaurs, and mammals.