Embryonic development in a petri dish

By growing mouse stem cells in a special gel, a research team succeeded to grow structures similar to parts of an embryo. The trunk-like structures develop the precursors for neural, bone, cartilage and muscle tissues from cellular clumps within five days. This could allow the investigation of the effects of pharmacological agents more effectively in the future -- and on a scale that would not be possible in living organisms.

source https://www.sciencedaily.com/releases/2020/12/201210145814.htm