Day 2: The Heart of the Matter
A 48 Hour Embryo
The chick embryo has almost doubled in length from
33 to 48 hours. The embryo has turned its head and
bent it toward the yolk, so that the left side of
its head rests on the yolk sac (like a pillow).
Eventually the rest of the body will twist to the
left so that the embryo is lying on its left side
atop the yolk. The eye can now be clearly seen. The
heart is now an S-shape and has begun to loop.
- Page 5 of 16 -