Final answer:
Amniotic eggs feature specialized membranes that allow amniote embryos to develop on land. These include the amnion for protection and hydration, the chorion for gas exchange, the allantois for waste storage, and the yolk sac for nutrition.
Step-by-step explanation:
The amniotic egg is a unique adaptation that allows amniotes to lay eggs on land without the risk of desiccation.
These membranes ensure that the embryo can develop in a terrestrial environment by providing protection, nutrition, and waste management. Their evolution marks a significant distinction between amniotes and other vertebrates like amphibians, which require moist environments for their shell-less eggs.
The membranes that contribute to the amniotic egg are the amnion, chorion, and allantois. The amnion is a thin membrane that surrounds and protects the embryo, providing a fluid-filled cavity that creates an aquatic environment for the embryo. The chorion is another protective membrane that surrounds the amnion. The allantois is involved in the exchange of gases and waste between the embryo and the eggshell, as well as storing waste products.