Human embryos are routinely cryogenically preserved, can be thawed and reimplanted to birth healthy human beings. Yet a blastocyst is roughly spherical, not homogenous, about 150-200 micrometers large, totals about 60 cells.
Also, even rabbit kidneys, which are a few centimeters large, can be preserved. Not very often, not very reliably so, but some could still function and sustain life for days after being thawed.
I believe such freezing is normally done at eight cells, no bigger. And you can in fact remove one of the eight cells and the child develops (apparently) normally—it’s the one sure-fire way to sex-test an embryo (recalling from memory).
What we’re talking about here is not making sure you can grow a brain at all (the embryo) nor making sure a filter can filter again (the kidney), but preserving the information that makes you you. It’s a different kind of problem from getting a filter to work again. The people who actually work with this stuff day to day and would love to be able to recover state from preserved neurons, even in principle, say it’s literally impossible with the present state of the art.
Odd.
Human embryos are routinely cryogenically preserved, can be thawed and reimplanted to birth healthy human beings. Yet a blastocyst is roughly spherical, not homogenous, about 150-200 micrometers large, totals about 60 cells.
Also, even rabbit kidneys, which are a few centimeters large, can be preserved. Not very often, not very reliably so, but some could still function and sustain life for days after being thawed.
I believe such freezing is normally done at eight cells, no bigger. And you can in fact remove one of the eight cells and the child develops (apparently) normally—it’s the one sure-fire way to sex-test an embryo (recalling from memory).
What we’re talking about here is not making sure you can grow a brain at all (the embryo) nor making sure a filter can filter again (the kidney), but preserving the information that makes you you. It’s a different kind of problem from getting a filter to work again. The people who actually work with this stuff day to day and would love to be able to recover state from preserved neurons, even in principle, say it’s literally impossible with the present state of the art.
Embryos in this context are a handful of cells and they end up reorganizing if they have a problem. And they don’t have delicate connections.
Kidneys are an interesting example but they are one of the simplest organs in the body.