The blastopore in a protostome develops into a mouth, whereas the blastopore in deuterostomes develops into an anal opening. Fate Map of the Blastoderm It should be possible to construct a fate map of. The key difference between protostomes and deuterostomes is the fate of the blastopore during their embryonic development. In addition, the leading edge cells have moved all the way to the anterior region of the embryo. The primitive node corresponds to the dorsal lip of the closed blastopore. The dorsal IMZ cells produce the axial mesoderm including notochord and somites. How many times has blastopore fate changed over the course of evolution Multiple times, though the exact. Also note that by the end of this process, the deep cells of the original marginal zone have spread to create a new middle layer of tissue within the embryo, the mesoderm. It is impossible to tell from the data provided.

illustrated to the left determinate cleavage (blastomere fate is fixed early in development). This results in preferential elongation of the embryo along the forming anterior-posterior axis. The blastopore becomes neither the mouth nor the anus. (3) Convergence and extension is highly asymmetric the dorsal IMZ cells (shown on the left here) converge and extend much more dramatically than the ventral and lateral regions of the IMZ. (2) The deep cells of the involuting marginal zone (shown in red here), then move into the interior via involution, as they undergo convergence and extension. The sequence can be divided into several steps: (1) As the dorsal lip of the blastopore forms, leading edge mesoderm (shown in orange here) is rotated up into the interior of the embryo as 'tongue' of material, probably as result of the apical constriction and bending of the blastopore lip by bottle cells. Gastrulation in Xenopus: Deep Fate MapThe animated sequence below provides an overview of the deep cells of the marginal zone during gastrulation in Xenopus. A blastomere isolated early in cleavage is able to from a whole individual (e.g. fate of the blastopore: protostome (annelida, arthropoda, mollusca): fate of the blastopore.

Blastopore fate