https://phys.org/news/2018-05-stem-cell-human-nervous.html > While studying embryonic development using animal embryos can provide useful insights about what happens during human development, human embryos grow differently even at this early stage. > "There is a critical need to establish embryonic developmental models using human cells. Not only could they advance our fundamental understanding of human development, they are also essential for regenerative medicine and for testing the safety of drugs and chemicals that pregnant women may need or encounter," said Jianping Fu, associate professor of mechanical engineering, who has been supervising the research.