The progression from a round ball of cells to an embryo with a head and a tail is one of the most critical steps in an organism’s development. But just how cells first start organizing themselves with directionality along this head-to-tail axis is hard to study because it happens in the earliest days of embryonic development, in the confines of a mammal’s uterus.
Click here for original story, How do developing spinal cords choose ‘heads’ or ‘tails’?
Source: Phys.org