What's the difference between blastosphere and blastula?
Blastosphere
Definition:
(n.) The hollow globe or sphere formed by the arrangement of the blastomeres on the periphery of an impregnated ovum.
Example Sentences:
Blastula
Definition:
(n.) That stage in the development of the ovum in which the outer cells of the morula become more defined and form the blastoderm.
Example Sentences:
(1) The activity was maximum at the 16-32-cell stage and then decreased to a minimum at the mesenchyme blastula stage.
(2) In Lytechinus pictus, the protein cannot be detected in eggs or in embryos until the mesenchyme blastula stage.
(3) In the present study, ectodermal explants from Xenopus blastulae were shown to have high affinity binding sites for 125I-aFGF (Kd = 1.4 X 10(-10) M).
(4) In blastula nuclei, over half of the RNA synthesis is effected by polymerase II (inhibited by alpha-amanitin), the proportion remaining roughly constant with increasing ionic strength.
(5) The embryos incubated in vitro at the from blastula stage are characterized by the sharp activation of protein synthesis and the vegetal-animal gradient of protein synthesis, as well as in the control embryos; such embryos gastrulate and proceed to primary differentiation.
(6) Scanning electronmicroscopy examination showed that the morphology of NCH blastula cells, which were obtained from the combination of Tilapia nucleus and goldfish cytoplasm, manifested obviously abnormal features and the cells were arrested at different stages of cell disintegration.
(7) Measurements of absolute transcript abundance show that collagen mRNA is present in blastula primary mesenchyme cells at 600-700 copies per cell and at about fourfold lower amounts in other mesenchyme cells.
(8) beta-Catenin, recognized by an anti-arm antibody, is also present in the fertilized egg and in blastula-stage embryos.
(9) The tandemly repeated genes were expressed at a higher rate in blastula than in gastrula stage relative to the single-copy gene, when the two genes were injected into sea urchin zygotes.
(10) As a result, there is a loss of the 'compacted' epithelial surface of the blastula, an inability to close a wounded surface and defective gastrulation.
(11) This aggregation is prevented by Fab fragments obtained by immunization with purified membranes from blastula embryos.
(12) In S. purpuratus, the Hbox1 gene product probably is not involved in initial specification of cell fate, as this message does not achieve a significant fraction of its peak abundance until almost hatching blastula stage, well after the time aboral ectoderm cells have initiated a tissue-specific program of gene expression.
(13) First, using eggs at the blastula stage, the proper concentration of cadmium to which the eggs should be exposed was estimated.
(14) Actinomycin D is excluded from unfertilized eggs and developing embryos of the sea urchin Arbacia punctulata until the blastula hatches.
(15) We are investigating the mechanism by which animal cells of an amphibian blastula are induced to differentiate as muscle after contact with blastula vegetal cells.
(16) By the early blastula stage, most of the maternal tubulin sequences were associated with polysomes.
(17) The dynamics of protein synthesis in the loach embryos has been studied by means of autoradiography at the stages of cleavage, blastula and gastrula.
(18) The same material added to dissociated blastula cells, or to embryos at the blastula stage, stimulates skeleton formation and pigment cell differentiation.
(19) New embryonic rRNA transcripts are first detectable at the very early blastula stage.
(20) The nucleus-like structure was partitioned into blastomeres during cleavage through a process of nuclear fission, and was maintained in a group of extraordinarily large blastomeres until the blastula stage.