... blastomeres', we found that 26-31% of them developed to term. However, our lack of understanding of the exact early cleavage pattern at that time meant that we could not have excluded with certainty `animal blastomeres' or others with greater developmental potency from the `vegetal blastomere' chimaeras...

... by Company of Biologists 1997 Sicyonia Crustacea Decapoda mitotic spindle cleavage pattern cell contact The essential element involved in determining embryonic cleavage patterns is the placement of the cleavage planes ( Freeman, 1983 ). It is widely accepted that the cleavage plane...

..., such embryos have a normal cleavage pattern, and they express both alkaline phosphatase and acetylcholinesterase, the markers of endoderm and muscle, respectively ( Bates and Jeffery, 1987 ; Jeffery, 1990b ). The results obtained in Styela indicate that the factor that promotes gastrulation is separable...

... did not affect formation of this latter axis. The cleavage pattern of the embryos that were deficient in posterior-vegetal cytoplasm (PVC) exhibited radial symmetry instead of the complicated bilateral symmetry of normal embryos. Detailed comparisons of cleavage patterns revealed the duplication...

... the dorsoventral axis can be artificially reversed at an early stage of development. We used this experimental system to examine the relationship between the specification of the dorsoventral axis and left/right asymmetry. bilateral asymmetry left/right axis dorsoventral axis embryo cleavage pattern...

...: Strongylocentrotus purpuratus, S. droebachiensis, Lytechinus pictus, Clypeaster rosaceus, Heliocidaris tuberculata and H. erythrogramma . The results indicate that there is no single relationship between the early cleavage pattern and the dorsoventral axis for all sea urchins; however, specific relationships exist...