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The Endowment for Human Development
The Endowment for Human Development
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Circadian Rhythms


4 months, 3 weeks

From The Biology of Prenatal Development.Buy Now

Script: Mula 19 na linggong paggalaw ng fetus, paghinga, at ang tibok ng puso ay nagsisimulang sumunod sa araw-araw na pag-inog na tinatawag na circadian rhythms.

All ages referenced to fertilization, not last menstrual period. One month = 4 weeks.
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