The blastopore is far more than just a hole; it is a fundamental biological landmark that determines the "body plan" of nearly all animals.
: Biologists use the fate of the blastopore to divide the animal kingdom into two massive groups: blastopore
: The blastopore becomes the anus (e.g., humans, frogs, starfish). The blastopore is far more than just a
: The blastopore becomes the mouth (e.g., insects, mollusks). mollusks). : In amphibians
: In amphibians, the "lip" of the blastopore acts as a primary signaling center that tells surrounding cells whether to become a head, a tail, or a nervous system. How It Forms Blastopore - an overview | ScienceDirect Topics
: It marks the spot where cells move inward to form the primitive gut, known as the archenteron .