AP BIOLOGY

Detailed explanation-1: -The amniotes had evolved a shelled egg, keratinized skin, and claws (among other traits) which allowed them to be successful at living on land.

Detailed explanation-2: -Amniotes are characterized by having an egg equipped with an amnion, an adaptation to lay eggs on land or retain the fertilized egg within the mother. Amniote embryos, whether laid as eggs or carried by the female, are protected and aided by several extensive membranes.

Detailed explanation-3: -The adaptations that make amniotes establish life on land are: the presence of rib cage ventilation for efficient air-breathing, internal fertilization, the amniotic egg protecting the embryo, and the skin being waterproof as there is no breathing through the skin.

Detailed explanation-4: -The amniotic egg allowed tetrapods to become completely terrestrial. In an amniotic egg, a membrane called the amnion surrounds the embryo and creates a fluid-filled cavity in which it develops. Other membranes aid in gas exchange, protection, and removal of wastes.

Detailed explanation-5: -The hard shell of the amniotic egg ensures that water and fluids will stay inside the egg, and this is the adaptation that allowed terrestrial animals to lay eggs on land. Other animals such as fish and amphibians lay jelly-coated eggs that have no shell, and therefore must be laid in the water or they will dry out.