: It is derived from the splanchnopleure, which consists of endoderm and splanchnic mesoderm. 2. Functional Diversity Across Species
The allantois is one of the four essential membranes of the —an evolutionary milestone that allowed vertebrates to transition from aquatic to terrestrial environments. It originates as a hollow, sac-like diverticulum from the hindgut (posterior region) of the embryo. allantois
: It is present in all amniotes, including reptiles, birds, and mammals. : It is derived from the splanchnopleure, which