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Birth

Birth is the act or process of bearing or bringing forth offspring. In mammals, the process is initiated by hormones which cause the muscular walls of the uterus to contract, expelling the fetus at a developmental stage when it is ready to feed and breathe. In some species the offspring is precocial and can move around almost immediately after birth but in others it is altricial and completely dependent on parenting. In marsupials, the fetus is born at a very immature stage after a short gestational period and develops further in its mother's womb's pouch. It is not only mammals that give birth. Some reptiles, amphibians, fish and invertebrates carry their developing young inside them. Some of these are ovoviviparous, with the eggs being hatched inside the mother's body, and others are viviparous, with the embryo developing inside her body, as in mammals.
bonbonniere - dfghjklòà
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bonbonniere

Added year ago by giusy

34

On a walk - little brother with a pram on a walk
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On a walk

Added year ago by andi

31

MODLITWA PRZED SNEM - dziecko tęskni za mamunią
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MODLITWA PRZED SNEM

Added over a year ago by WIESŁAW

38

modne dziecko - mama i dziecko uśmiechnięte
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modne dziecko

Added over a year ago by Rozalinda

30

dziecko to ty - uśmiech zdrowego dziecko
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dziecko to ty

Added over a year ago by Romina

26

blizniaki jednojajowe - wózek,głowy,fajne oznakowanie
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blizniaki jednojajowe

Added over a year ago by wieslawa

17