Definition of blastopore in US English:



  • The opening of the central cavity of an embryo in the early stage of development.

    • ‘Arrow worms were considered deuterostomes based on their tripartite coelom and the retention of the blastopore to form the anus.’
    • ‘More accurately, the blastopore elongates along the future ventral midline and the mouth and anus develop at opposite ends.’
    • ‘In the complementary category of the protostomes, which includes annelids and arthropods, the blastopore develops into the mouth.’
    • ‘One group, including amphioxus, lampreys, sturgeons and amphibians, displays the primitive condition, with holoblastic eggs and involution of the endoderm through a blastopore.’
    • ‘Both the fate of the blastopore and early embryonic cleavage patterns vary considerably among the Bilateria and have not been assessed experimentally in many species.’