Very early in pregnancy (as in earlier than 30 days), the neural plate - that's a flat-type structure that will become the brain and spinal cord - forms a groove and rolls up into a tube that runs the length of the entire embryo. One end of the tunnel starts to swell; this is where the brain will form. The rest of the tube becomes the spinal cord.
By eight weeks, as the spinal-cord part of the tube is fused together, we can already see three distinct parts of the brain - the fore brain, mid brain, and hind brain. All of this swelling has started to form the basis of some of the neurological structures that you may have already heard of - things like the medulla, the basal ganglia, the thalamus, and the cerebral cortex.
Very early in pregnancy (as in earlier than 30 days), the neural
plate - that's a flat-type structure that will become the brain and
spinal cord - forms a groove and rolls up into a tube that runs the
length of the entire embryo. One end of the...
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Dr. Michael Roizen answered:Very early in pregnancy (as in earlier than 30 days), the neural plate - that's a flat-type structure that will become the brain and spinal cord - forms a groove and rolls up into a tube that runs the length of the entire embryo. One end of the tunnel starts to swell; this is where the brain will form. The rest of the tube becomes the spinal cord.
Find out more about this book: YOU: Having a Baby: The Owner's Manual to a Happy and Healthy Pregnancy
