amniote

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amniote

 [am´ne-ōt]
any animal that develops an amnion.

amniote

/am·ni·ote/ (am´ne-ōt) any member of the group of vertebrates that develop an amnion, including reptiles, birds, and mammals.

amniote

(ăm′nē-ōt′)
n.
Any of numerous vertebrates of the group Amniota, characteristically having an amnion during embryonic development and including the reptiles, birds, and mammals.

amniote

any land vertebrate which possesses an AMNION, CHORION and ALLANTOIS, i.e. reptiles, birds and mammals.

amniote

any animal with amnion.

Patient discussion about amniote

Q. what does it mean when an ultrasound shows an empty amniotic sac and no baby?

A. This exact thing happened with my friend who is now 22 weeks with her first baby. She had 2 additional sacs - both empty - and the doctor said that the pregnancy had probably started out as triplets but that only one of the embryos had actually established and continued to grow.

Her doctor said it is very common for a woman to have more than one egg fertilize but that in most cases the pregnancy continues as a singleton only. She told my friend that the empty sacs would just disappear through time (which they did) and that they posed no danger to her baby.

More discussions about amniote
References in periodicals archive ?
Hylonomus lyelli, meaning "forest dweller", named in honour of his mentor and friend, Sir Charles, a century and a half later was proclaimed Nova Scotia's Provincial fossil and remains the earliest known amniote in the fossil record (Carroll 1964, 1970; Reisz 1997; Clack 2002).
We can conclude, therefore, that the subsequent diversification of Palaeozoic amniotes and the rise of small and large omnivorous, herbivorous and predatory forms arose from these modest beginnings," they added.
Odd as they are, turtles clearly belong to the lineage of amniotes, which includes mammals, birds and reptiles.
Any features shared by all three embryos probably came from distant common ancestors of all amniotes, the researchers note.
For example, humans are included in the following nested clades (using the informal names): eukaryotes, animals, deuterostomes, vertebrates, gnathostomes, tetrapods, amniotes, mammals, eutherians, primates, monkeys, apes, and great apes (see Dawkins, 2004 for more information on the ancestry of humans).
Today's birds have the smallest genomes among amniotes, the animal group that includes mammals, reptiles, and birds.
This creature is the first real evidence of a terrestrial animal that we have, and yet it looks like a close relative of amniotes, if not an amniote itself, which is a bit of a stunner really," says Clack.
Further study of the specimen may help clarify the evolutionary relationship between amniotes and nonamniotes, he says.