In the tug-of-war between mother and baby, the placenta is a life-giving referee
The womb isn’t as welcoming a space for a developing offspring as you might imagine. Indeed, from the moment an embryo is implanted in the mother’s womb, her immune system views the foreign body as something of an invader. Thereafter, the relationship between mother and developing baby is at least partially defined by a biological war over resources. In this clash, the placenta serves as a life-giving intermediary between mother and offspring, allowing for the transport of nutrients while keeping blood supplies entirely separate. With a surrealist-inspired touch, this animation by Diana Gradinaru for the Royal Institution of Great Britain traces the many functions of this fascinating, essential and short-lived organ, as well as its viral evolutionary origins.

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