- published: 14 Oct 2014
- views: 170529
The placenta is an organ that connects the developing fetus to the uterine wall to allow nutrient uptake, waste elimination, and gas exchange via the mother's blood supply. "True" placentas are a defining characteristic of eutherian or "placental" mammals, but are also found in some snakes and lizards with varying levels of development up to mammalian levels. Note, however, that the homology of such structures in various viviparous organisms is debatable at best and, in invertebrates such as Arthropoda, is definitely analogous at best. However, a recent publication describes what amounts to a phylogenetically analogous, but physiologically and functionally almost identical structure in a skink. In some senses it is not particularly surprising, because many species are ovoviviparous and some are known as examples of various degrees of viviparous matrotrophy. However, the latest example is the most extreme to date, of a purely reptilian placenta directly comparable to a eutherian placenta.
The Placenta: Its Development and Function
Would You Eat Your Placenta?
Delivering Placenta after Birth (real life shootage)
Meet the placenta
Examining the Placenta
Examining the Placenta - Childbirth Series
Manual Removal of Placenta
The Placenta
PARTO NORMAL E RETIRADA DA PLACENTA
The Amazing Placenta
O QUE VENHO LHE CLAMAR
É SOMENTE UM TEMPO A MAIS
PRA QUE EU
POSSA LHE EXPLICAR
O QUE PRA VOCÊ TANTO FAZ
OLHE PRAS CRIANÇAS NO PARQUE
ELAS ESTÃO FELIZES
AGORA ESTÃO BRINCANDO
MAS LOGO IRÃO CRESCER
E TERÃO QUE APRENDER A SOFRER
OU SEJA APRENDER A VIVER
E APRENDER A SOFRER
OU SEJA APRENDER A VIVER
ONTEM AMEI TUA
PRESENÇA AQUI
EU APRENDI A VIVER
HOJE ODEIO
A TUA AUSÊNCIA AQUI
EU TIVE QUE APRENDER A SOFRER
EU TIVE QUE APRENDER A SOFRER
OU SEJA APRENDER A VIVER
E APRENDER A SOFRER
OU SEJA APRENDER A VIVER...
VIVENDO APRENDO A AMAR
AMANDO A SOFRER
SOFRENDO APRENDO A VIVER
SOFRENDO APRENDO A AMAR
VIVENDO A SOFRER
AMANDO APRENDO A VIVER