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Learn about Embryonic Stem Cells

What is an embryonic stem (ES) cell?

What do embryonic stem cells do?

What contains embryonic stem cells?
Embryos that are 3 to 5 days old contain embryonic stem cells. (1)
At this stage, an embryo is called a blastocyst and has about 150 cells. (1)

1. https://www.mayoclinic.org/tests-procedures/bone-marrow-transplant/in-depth/stem-cells/art-20048117