A mother-to-be provides the unborn baby with food and
oxygen from the

placenta

The fetus is connected by the umbilical cord to the placenta, the organ that develops and implants in the mother's uterus during pregnancy. Through the blood vessels in the umbilical cord, the fetus receives all the necessary nutrition, oxygen, and life support from the mother through the placenta.

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answer; more than 80% percent of adults;