During embryonic development, the nervous system begins as a single strip of specialized ectoderm, the neural plate, which folds on itself to form the neural tube that later becomes the spinal chord and the brain, while nerves grow out of it towards the other parts of the body. It never happens that two separate pieces of neural tissues become attached.
AFAIK, If you inject stem cells in the severed spine of a rat and play with growth chemical signals, you may get the formation of new neural tissue that makes more or less random connections with the existing tissue which may recover some function (if it doesn’t cause cancer), but that doesn’t seem to be a precise process.
I wonder whether the lizard tail regeneration involves the extension of a functional spinal chord.
Perhaps, but I don’t think it’s so easy.
During embryonic development, the nervous system begins as a single strip of specialized ectoderm, the neural plate, which folds on itself to form the neural tube that later becomes the spinal chord and the brain, while nerves grow out of it towards the other parts of the body. It never happens that two separate pieces of neural tissues become attached.
AFAIK, If you inject stem cells in the severed spine of a rat and play with growth chemical signals, you may get the formation of new neural tissue that makes more or less random connections with the existing tissue which may recover some function (if it doesn’t cause cancer), but that doesn’t seem to be a precise process.
I wonder whether the lizard tail regeneration involves the extension of a functional spinal chord.