An embryo is called a(n) ________ when it reaches around 100 cells, and appears to be a hollow, ball-like structure.
A) endoderm
B) trophoblast
C) inner cell mass
D) blastocyst
E) zygote

Question

Quizplus · Accepted Answer

When an embryo reaches around 100 cells, it becomes a blastocyst which is a hollow, ball-like structure consisting of the trophoblast and the inner cell mass. The other options listed are embryonic tissues or earlier developmental stages.

An Embryo Is Called A(n) ________ When It Reaches Around