Question

fill in the blank question
the stage of development begins at the beginning of the third week of gestation.

Explanation:

In human development, the embryonic stage starts at the beginning of the third week of gestation. Before this, the zygote undergoes cleavage and forms a blastocyst (the pre - embryonic stage). During the embryonic stage (weeks 3 - 8 of gestation), major organ systems begin to form through processes like gastrulation (formation of three germ layers: ectoderm, mesoderm, endoderm) and organogenesis.

Answer:

embryonic