In amphibians, deep cells underlie the superficial epithelial cells of the animal cap and marginal zone. Reaction- Wave of exocytosis that occurs as the cortical granulesįuse with the egg plasma membrane and release their contents afterĬytokinesis- Division of the cytoplasm during mitosis.ĭeep cells -Generally, non-epithelial cells in a vertebrate embryo. Thickened coelomic epithelium of developing gonads. Gel-like cytoplasmic layer just below the egg plasma membrane. Return to Gastrulation- More Movements or Sagittalįate Map or Time Lapse or Planar InductionĬortex- 1. Wave- Chain reaction of intracellular Ca2 + release and uptakeĬell cycle- Period between the formation of a cell by the division of its parent cell and the formation of two new cells by cell division.Ĭonvergence and extension- Convergence of an epithelial sheet toward a central site, followed by its extension along a single axis through forceful intercalation of the cells of the epithelium. Usually consists of a hollow ball of cells.Ĭells - Epithelial cells that temporarily become bottle-shaped, owing to the contraction of their apical margins and the expansion of their basal margins found at the site of initiation of gastrulation in amphibian embryos. In animals whereĬleavage (cell division) involves the whole egg, the blastula
The end of cleavage but before gastrulation. In Xenopus, the dorsal bottle cells constrict first, creating a crescent of pigment resembling a frown.īlastula-Stage of embryonic development of animals near The blatoporal pigment line forms as a result of the apical constriction of bottle cells, thereby concentrating the pigment granules near the apex of each of the bottle cells, and marks the initial phase of formation of the blastopore lip. Pigment line-The first visible sign on the surface of the amiphibian embryo that gastrulation is underway. The groove presumably results from the invagination producedīy apical construction, as well as the basal expansion of theīasal ends of the bottle cells, which forces nearby tissue to Groove-The groove formed as result of the formation of bottleĬells. One of the cells produced as the result of cell division, cleavage, In the animal half and yolk, where present, largely in the vegetalĪnterior-posterior axis - Body axis extending from the anterior to the posterior pole of a bilaterally symmetric embryo (or animal).īy the endoderm during gastrulation will later become the gutĪxial mesoderm -the mesodermal tissue that gives rise to the notochord and somites.īlastocoel- Fluid-filled cavity that forms in the embryo after the morula stage. Of substances along this axis, with pigment granules often concentrated In many eggs there is also a graded distribution During meiosis of the oocyte the polar bodies areĮxpelled at animal pole. Pole, with the animal-vegetal axis between the poles passing through To the nucleus is the animal pole, and the other is the vegetal Pole-In most animal oocytes the nucleus is not centrally placedĪnd its position can be used to define two poles. Injected with thyroid or pituitary gland extract.Īnimal cap-Pigmented animal hemisphere of the amphibian blastula. The neotenous,Īquatic axolotl will metamorphose into the terrestrial form if May retain the larval form, but can reproduce.
Growth of cells, particularly bacteria and some cancer cell lines.Īxolotl (amphibian). From seaweed (Rhodophyceae) and used as an inert support for the
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