I would expect the interphase period of stem cells to be short since embryonic stem cells undergo very rapid changes; thus interphase in them is short.
Embryonic stem cells (ES cells) are pluripotent stem cells derived from the inner cell mass of a blastocyst, an early-stage pre implantation embryo. Human embryos reach the blastocyst stage 4–5 days post fertilization, at which time they consist of 50–150 cells.
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