from The American Heritage® Dictionary of the English Language, 4th Edition
- n. An early embryonic form produced by cleavage of a fertilized ovum and consisting of a spherical layer of cells surrounding a fluid-filled cavity. Also called blastosphere.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An early form in the development of an embryo, consisting of a spherical layer of cells filled with fluid; a blastosphere.
from the GNU version of the Collaborative International Dictionary of English
- n. That stage in the development of the ovum in which the outer cells of the morula become more defined and form the blastoderm.
from The Century Dictionary and Cyclopedia
- n. In embryology: An embryo of one of the Metazoa, in the stage in which it consists of a sac formed of a single layer of cells.
- n. In Haeckel′ s vocabulary of embryology, same as blastosphere, .
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. early stage of an embryo produced by cleavage of an ovum; a liquid-filled sphere whose wall is composed of a single layer of cells; during this stage (about eight days after fertilization) implantation in the wall of the uterus occurs
It’s not a solid ball but a hollow one, and it is called the blastula.
The only people politicizing the use of embryonic stem cells are those who claim that a blastula, which is an invisible to the naked eye group of cells an embryo is not the same thing as a fetus, is a human.
The globular wall of the blastula is a real blastoderm, and consists of homogeneous (blastodermic) cells; it is not yet differentiated into the two primary germinal layers.
The development of most animals is characterized by distinctive stages, including a zygote, formed by the product of the first few division of cells following fertilization; a blastula, which is a hollow ball of cells formed by the developing zygote; and a gastrula, which is formed when the blastula folds in on itself to form a double-walled structure with an opening to the outside, the
After the egg is fertilized it becomes a blastula, which is free swimming.
If we say that a blastula is a human being, I can't even imagine the scale of the tragedy we've engendered just by attempting to bring new life into the world.
The visceral embryonic vesicle (blastocystis or gastrocystis) of a rabbit (the "blastula" or vesicula blastodermica of other writers), a outer envelope (ovolemma), b skin-layer or ectoderm, forming the entire wall of the yelk-vesicle, c groups of dark cells, representing the visceral layer or entoderm.
The characteristic embryonic form that the developing mammal now exhibits has up to the present usually been called the "blastula"
What is called the "blastula" of the mammal and the real blastula of the amphioxus and many of the invertebrates are totally different embryonic structures.
You will never sell most people on the concept zygote = blastula = embryo = fetus = baby, which is what is required of them to even “get” your “intrinsic connection.”
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