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The allantois, yolk sac and part of chorion.
Jaunita Hand
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What part of the chicken egg acts as placenta in mammals?
The allantois, yolk sac and part of chorion.
Do mammals develop in egg or in uterus?
Placental mammals and marsupials develop in a placenta within the uterus before being delivered. Monotremes develop in an egg.
Does the egg stick to the placenta in the womb?
The placenta is created by the egg.
Where do most mammals grow before they're born?
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.
What are the different orders under the class Mammals?
Monotremes (Monotremes are primitive, egg-laying mammals)Marsupials (Marsupials are mammals whose babies are born very immature)Placental mammals (Placental mammals are advanced mammals whose unborn young are nourished through a placenta)
Why can't humans lay eggs?
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.
Where do baby mammals develop?
I the mammal is a monotreme, it developes in an egg. If the mammal is in the marsupial group, it develops in a pouch on its mother. If it is a placental mammal, it develops in the placenta.
What are the Advantages of placental development?
Development of the placenta gave mammals the ability to carry its young internally, which provided an advantage over egg laying rivals.
Does the ovaries in the women make the placenta?
No - the placenta grows around the fetus in the uterus as part of the pregnancy. The ovaries just supply hormones and the egg that gets fertilized.
How do birds develop without a placenta?
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.
Do ocelots mate?
No. Ocelots are placental mammals, meaning they give birth to live young. The only egg-laying mammals (monotremes) are platypuses and echidnas.
Is a kangaroo a monotreme?
No. Kangaroos are marsupials whose young are attached in the uterus with a placenta, and complete development in a pouch. Monotremes (the Platypus and Echidna) are egg-laying mammals.
