Amniotes are tetrapod vertebrate animals belonging to the clade Amniota, a large group that comprises the vast majority of living terrestrial and semiaquatic vertebrates. Amniotes evolved from amphibious stem tetrapod ancestors during the Carboniferous period.

Amniota, a group of limbed vertebrates that includes all living reptiles (class Reptilia), birds (class Aves), mammals (class Mammalia), and their extinct relatives and ancestors.

2019年4月17日 · Amniotes are vertebrate organisms which have a fetal tissue known as the amnion. The amnion is a membrane derived from fetal tissue which surrounds and protects the fetus. The amnion can be found within the egg, as in lizards and birds, or the amnion can simply enclose the fetus within the uterus.

The meaning of AMNIOTE is any of a group (Amniota) of vertebrates that undergo embryonic or fetal development within an amnion and include the birds, reptiles, and mammals.

2018年1月31日 · Amniotes (Amniota) are a group of tetrapods that includes birds, reptiles, and mammals. Amniotes evolved during the late Paleozoic era. The characteristic that sets amniotes apart from other tetrapods is that amniotes lay eggs that are well-adapted to survive in a …

Surrounding and protecting the embryo is the amnion, filled with amniotic fluid, and providing the embryo with a stable fluid environment. The allantois performs two very important functions for the embryo, providing for gas diffusion, and removal of wastes.

2021年2月28日 · Amniotes are a clade of tetrapod vertebrates comprising the reptiles, birds, and mammals. 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.