WEBVTT

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Our journey of life began as a single-celled zygote—

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the product of the fusion of the genetic material from our father’s sperm cell and our mother’s ovum.

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During the next 2 weeks—the germinal phase of prenatal development—that single cell became a mass of cells,

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doubling again and again as it moved down the fallopian tube before implanting in the wall of the mother’s uterus.

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During weeks 3 through 8—the embryonic phase—we began to draw our nutrients from our mother’ blood,

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and the general-purpose cells differentiated into specialized cells, allowing our organ systems to begin forming.

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By the time we reached the fetal phase at 9 weeks after conception, all of our organ systems were present, although they were not yet fully functional.

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During the time remaining until birth (usually around 38 weeks after conception), the fetus grew dramatically

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and each of the organ systems continues to mature, preparing the fetus for life outside the womb.