Question Detail
Question
What critical structure forms during gastrulation that determines the body axis of the embryo?
Correct Answer
Option C is the correct answer.
Detailed Explanation
In avian and mammalian embryos, the primitive streak is a groove that forms on the epiblast surface. It establishes the anterior-posterior axis and is the site where cells migrate inward during gastrulation to form the germ layers.
Hint
It's the 'organizer' region for axis formation.