It is a thin but tough transparent pair of membranes that hold a developing embryo (and later fetus) until shortly before birth. The inner of these membranes, the amnion, encloses the amniotic cavity, ...

Other extra-embryonic folds expand up over the embryo to form the amniotic folds. The amnion and chorion develop together as upwardly projecting amniotic folds, eventually closing over the dorsal ...

Other extra-embryonic folds expand up over the embryo to form the amniotic folds. The amnion and chorion develop together as upwardly projecting amniotic folds, eventually closing over the dorsal ...

A stem-cell derived human embryo model showing blue cells (embryo), yellow cells (yolk sac) and pink cells (placenta). Scientists have grown an entity that closely resembles an early human embryo ...