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 ?
Odd as they are, turtles clearly belong to the lineage of amniotes, which includes mammals, birds and reptiles.
At the heart of Carroll's theory lies the amniote egg, which has a series of membranes not present in the simpler eggs of frogs and salamanders.
It suggests that we, and maybe amniotes in general, are much more alone in the lack of an ability to regenerate limbs," she says.
The vertebrates, for example, are subdivided into amniotes (reptiles, birds, and mammals) and anamniotes (fishes and amphibians) based on whether they possess an amnion--a protective embryonic coveting.
It feeds mainly on fishes, frogs and aquatic crustaceans; amniotes, in particular terrestrial ones, are seldom taken.
But if the amniotes are considered, Australia has the highest number of these species under threat among all developed nations (IUCN, 2004b).
It covers gametogenesis and fertilization, lineage tracking, oogenesis and other early development, development in amphibians and amniotes, vertebrate organogenesis including metamorphosis, plant development, morphogenesis, regulations of gene expression, and evolution.
Our evolutionary roots--the amniota-began a great divergence when a few amniotes crawled out of a primordial sea and left their finned relatives behind.
The human embryonic circulatory system is a modification of that used in other amniotes, such as birds and reptiles.
They have long believed two groups of animals - amphibians and amniotes - evolved from common ancestors hundreds of millions of years ago.
Neocortex evolved from a more primitive cortex, likely present in the ancestors of all amniotes.