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 ?
Any features shared by all three embryos probably came from distant common ancestors of all amniotes, the researchers note.
See Appendix for an overview, including a glossary of terms, of forebrain organization in amniotes.
Neocortex evolved from a more primitive cortex, likely present in the ancestors of all amniotes.
Today's birds have the smallest genomes among amniotes, the animal group that includes mammals, reptiles, and birds.
The relationships among the amniotes and the basic relationships within the mammals showed differences.
The effect was observed mainly in plants and amphibians, and it was supposed that it was absent in amniotes, which have a smaller average genome size and smaller differences among species (Olmo 1983; Szarski 1983; Olmo et al.
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.
Bennett and Ruben 1979), then this relationship should hold at least for all amniotes.
In free-living organisms, such as smelts and eels among teleostean fishes, caecilians among amphibians, and snakes among amniotes, secondary loss of characters and the resulting simplification in morphology is called evolutionary specialization, not degenerate evolution.
Further study of the specimen may help clarify the evolutionary relationship between amniotes and nonamniotes, he says.
Protein sequences indicate that turtles branched off from the amniote tree after mammals.