Placenta is used by certain mammals to nurture embryos that will develop into a baby that will be born live. Birds, however, don't give birth to live young. Instead, they lay eggs, and the embryo inside the egg is nurtured by a nutrient and energy rich yolk sac, rather than by a placenta.
Birds develop internally, which means inside the creatures body.
Placenta comes out after each kitten.
Birds develop internally, within the egg, where they undergo rapid physical changes before hatching. The egg provides protection and nutrients for the developing embryo, allowing it to grow and develop until it is ready to hatch. Once hatched, the bird continues to grow and mature externally in its environment.
the chicken's placenta, as opposed to a human placenta, does not connect the mother to the child. instead, it connects the mother and the egg. the placenta extends from the mother's anus to the top of the egg. this is why the chicken sits on her eggs.
Posterior placenta is when the placenta is located at the back of the motherÃ?s uterus. Placenta praevia means the placenta has not moved up towards the top of the uterus to get ready for birth. Grade 2 means the placenta is near the cervix but not blocking it.
in the egg
Animals that do not develop in a placenta will develop outside of the uterus rather than in. Kangaroos and Koalas use pouches to develop their young.
They develop by feeding from the yolk of the egg that the frog has laid and that is the equivalent of a placenta.
The same way every animal before mammals evolved did it. The egg contains a yolk loaded with nutrients that they live off and the shell has pores that let air in and carbon dioxide out for their respiration.
Instead of getting oxygen and nutrients directly from a mother, the bird egg contains these elements in the materials found around the bird embryo. Reptiles and amphibians have similar processes for supplying the embryo.
Yes, twins can share a placenta during pregnancy. This occurs when identical twins develop from a single fertilized egg and share the same placenta.
Humans are placental mammals, meaning that they develop with the embryo attached to a placenta that allows it to exchange waste and nutrients with the mother. The placenta would not be able to function inside an egg.
Most mammals are placental mammals: they develop in a placenta before birth. Marsupials also develop in a placenta, but they are delivered much earlier and the placenta is less developed. Monotremes develop within an egg, which is kept inside the mother for some time before it is laid. It hatches several days later.
Placental mammals and marsupials develop in a placenta within the uterus before being delivered. Monotremes develop in an egg.
The young of placental mammals develop within a placenta. The placenta is a thick membrane that is connected to the inside of the uterine wall. The umbilical cord connects the baby to the inside wall of the placenta. Nutrients and oxygen go from the mother's blood stream through the placenta, down the umbilical cord, and into the baby. The baby releases waste products and carbon dioxide, which travel up the umbilical cord, through the placenta and into the mother's blood stream.
Birds develop internally, which means inside the creatures body.
They did not. Mammals evolved independently of birds.