The respiratory function of embryo is performed by
Chorion
Amnion
Allantois
Yolk sac
The permeability of the human placenta to macro-molecules is evidenced by the presence of following in foetal blood
The shock absorber fluid of the developing embryo is known as
When mouth develops from blastopore, the organism is called
The mammalian primitive streak gives rise to
Human placenta is derived from