amniote

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amniote

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

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.

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 ?
canicula the DTmesV formed in the mesencephalon early (Figures 4(b) and 4(c)), reminiscent of amniotes [4, 5].
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).
Higher developmental temperatures generally lead to more trunk vertebrae in amniotes (Fox et al.
"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.
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).
In their review of the evolution of intelligence, Emery and Clayton (2004) note that "divergent brain evolution" has resulted in substantial differences across amniotes in brain organization at the cellular level.
Examination of the patterns of neural and somatic morphogenesis in additional outgroups (e.g., Aves, Chelonia, Squamata, or Crocodylia) would aid in determining major patterns of cranial development and evolution in amniotes. However, these groups have each undergone considerable independent evolution since their last common ancestor with mammals (which lived over 300 M.Y.B.P.; Carroll 1988) and thus cannot be assumed to be representative of a primitive condition.
B- Traces ascribable to Amniotes; Captorhinomorpha or gracile reptiles with Hyloidichnus major (Heyler and Lessertisseur, 1963), Haubold, 1971; Varanopus curvidactylus Moodie, 1929 (Sarjeant, 1971), Microsauripus acutipes Moodie, 1929 (Sarjeant, 1971); Varanopus rigidus Gand, 1989; Pelycosauria with Dimetropus leisnerianus (Geinitz, 1863) Haubold, 1971, Dimetropus nicolasi Gand and Haubold, 1971 being its undertrack; Diadectids (Voigt, 2004): cf.