An Embryo with Meroblastic Cleavage,extraembryonic Membranes,and a Primitive Streak Must

Question

An embryo with meroblastic cleavage,extraembryonic membranes,and a primitive streak must be that of
A)an insect.
B)a fish.
C)an amphibian.
D)a bird.
E)a sea urchin.

Accepted Answer

The presence of meroblastic cleavage (incomplete division of the egg) is characteristic of birds. Additionally, the presence of extraembryonic membranes (such as the amnion and chorion) and a primitive streak (a structure that forms during gastrulation) are also unique to birds.