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Fetal Circulation

10 videos
At one stage or another in development, every friend you know had gill slits and a tail. Pretty crazy thought, huh? Fetal development is incredible, and it’s important to understand exactly how it happens. The structure and function of the circulatory system is incredibly complex, and fetuses are no exception. Find out how the heart and circulatory system work in the fetus!

Meet the placenta!

VIDEO 12:29 minutes
Learn how the needs of the fetus are met by the placenta, which is a special organ that belongs to both the mother and the fetus! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Umbilical vessels and the ductus venosus

VIDEO 12:33 minutes
Watch as fetal blood goes through umbilical vessels and takes a shortcut through the Ductus Venosus to make it back to the heart. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Flow through the heart

VIDEO 7:51 minutes
Learn how blood flows through the heart, and understand the difference between systemic and pulmonary blood flow. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Hypoxic pulmonary vasoconstriction

VIDEO 9:14 minutes
Watch how blood gets diverted away from alveoli with low oxygen levels. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Foramen ovale and ductus arteriosus

VIDEO 14:13 minutes
Watch how the fetal heart allows blood to simply bypass the lungs altogether using the Foramen Ovale and the Ductus Arteriosus! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Fetal hemoglobin and hematocrit

VIDEO 14:32 minutes
Although mom controls the oxygen source, the fetus has a couple of clever tricks to get the most oxygen possible! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Double Bohr effect

VIDEO 10:34 minutes
Learn how there are two distinct Bohr effects happening at the same time in the placenta. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Fetal circulation right before birth

VIDEO 11:53 minutes
Watch how the blood flows through the fetal circulation and compare it to what happens in the baby's body. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Baby circulation right after birth

VIDEO 13:25 minutes
Watch how the blood flows through the baby's circulation and compare it to what happens in the fetus. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Fetal structures in an adult

VIDEO 8:17 minutes
Find out what happens to those nifty fetal structures once we get older. Rishi is a pediatric infectious disease physician and works at Khan Academy.