Study: How placentas evolved in mammals

The fossil record tells us about ancient life through the preserved remains of body parts like bones, teeth and turtle shells. But how to study the history of soft tissues and organs, which can decay quickly, leaving little ...

Maternal microbiome promotes healthy development of the baby

A mother's gut microbes can help in the development of the placenta, and the healthy growth of the baby—according to new research from the University of East Anglia, the Quadram Institute and the University of Cambridge.

Male seahorses develop placentas to support their growing babies

Supplying oxygen to their growing offspring and removing carbon dioxide is a major challenge for every pregnant animal. Humans deal with this problem by developing a placenta, but in seahorses—where the male, not the female, ...

Biologists discover a new type of placental structure in animals

The Cyclostomata is an ancient group of aquatic colonial suspension-feeders from the phylum Bryozoa. The fact that they have unique placentae has been discovered by researchers at St Petersburg University and the University ...

Cause of oversized placentas in cloning found after two decades

One reason a technique for cloning animals often results in oversized placentas, and hence failed births, has been uncovered in mice by an all-RIKEN team. This finding will help improve the success rate of the cloning method ...

Predation risk drives the evolution of the placenta

An international team of scientists led by assistant professor Bart Pollux from Wageningen University & Research has showed that predators are driving the evolution of more complex placentas. They studied populations of the ...

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Placenta

The placenta is an organ unique to mammals that connects the developing fetus to the uterine wall. The placenta supplies the fetus with oxygen and food, and allows fetal waste to be disposed of via the maternal kidneys. The word placenta comes from the Latin for cake, from Greek plakóenta/plakoúnta, accusative of plakóeis/plakoús - πλακόεις, πλακούς, "flat, slab-like", referring to its round, flat appearance in humans. Protherial (egg-laying) and metatherial (marsupial) mammals produce a choriovitelline placenta that, while connected to the uterine wall, provides nutrients mainly derived from the egg sac. The placenta develops from the same sperm and egg cells that form the fetus, and functions as a fetomaternal organ with two components, the fetal part (Chorion frondosum), and the maternal part (Decidua basalis).

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