Only two weeks after fertilization, the first sign of the formation of the 3 axes of the human body (head/tail, ventral/dorsal, and right/left) begins to appear. At this stage, known as gastrulation, ...

Microscopy image of a PGA at day 8 showing the early tissues supporting the embryo, including the amniotic sac and the yolk sac-like structures, surrounded by (extra-embryonic) mesoderm tissue.

New biophysics research adds to our knowledge about the origins of left-right asymmetry in the body. Most animals, including humans, have bilateral symmetry, which means our bodies are pretty ...