from The American Heritage® Dictionary of the English Language, 4th Edition
- n. The layer of cells that develops on the surface of the yolk in an avian or reptilian egg and gives rise to the germinal disk from which the embryo develops.
- n. The layer of cells formed by the cleavage of a fertilized mammalian egg. It later divides into the three germ layers from which the embryo develops.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. The germination point in an ovum from whence the embryo develops.
from the GNU version of the Collaborative International Dictionary of English
- n. the early embryo developing from a blastodisc, after the blastocoel has formed.
- n. in an insect embryo, the layer of cells that surrounds the internal mass of the yolk.
from The Century Dictionary and Cyclopedia
- n. In embryology, the primitive membrane or layer of cells resulting from the subdivision of the germ (the segmentation of the vitellus or yolk).
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a layer of cells on the inside of the blastula
This white mark will be perfectly round if the egg is fertile (called a blastoderm).
If vesicles are then generated from this proto-ER/Golgi, a plasma membrane can be formed on an existing cytoskeleton, a process similar to the formation of the cellular blastoderm in Drosophila and similar to the addition of vesicle to the current plasma membrane.
The syncytial blastoderm in Drosophila show that the nuclei can independently divide and later form a multicellular embryo.
For my first experiments in his lab, I set out to investigate whether cells at the blastoderm stage were already determined to form specific discs.
My plan was to remove single cells from defined regions of the blastoderm and culture them in adult abdomens surrounded by genetically marked "feeder cells."
Both studies suggested that segmental units might be established as three to four cell wide stripes at the blastoderm stage.
Because legs were derived from different segments, my results suggested that if blastoderm cells were determined for anything, they were determined for segments rather than discs.
In contrast to the restricted clones produced by irradiation of larvae, such clones extended between the wing and leg of the adult fly, indicating that the blastoderm cell that gave rise to the clone could not yet have been determined with respect to either disc.
This experiment was important in showing that the primordia of individual segments in the blastoderm stage were no more than three cells wide.
Schardin, we did a fate map for the larval cuticle using laser ablations of Drosophila blastoderm cells.