ClipArt ETC
Diagram of fecundated egg. a, umbilical vesicle; b, amniotic cavity; c, allantois.

Fecundated Egg

Diagram of fecundated egg. a, umbilical vesicle; b, amniotic cavity; c, allantois.

Human embryo of fifth week with umbilical vesicle. The human umbilical vesicle never exceeds the size of a small pea.

Embryo of Fifth Week

Human embryo of fifth week with umbilical vesicle. The human umbilical vesicle never exceeds the size…