In deuterostomes, what does the blastopore develop into?

In deuterostomes, the blastopore, which is the initial opening that forms during the early stages of embryonic development, develops into the anus. This is one of the key distinguishing features of deuterostome development, contrasting with protostomes, where the blastopore typically becomes the mouth.

During early embryonic development, the process of gastrulation establishes the body plan, including the formation of the gut. In deuterostomes, after the blastopore develops into the anus, a second opening then forms to create the mouth, which is often at a different site. This pattern is seen in organisms such as echinoderms (e.g., sea stars) and chordates (e.g., vertebrates), where the relationship among the gut, mouth, and anus follows this specific developmental sequence.

Understanding this characteristic is important for grasping the evolutionary relationships between deuterostomes and protostomes, and how their developmental pathways shape their anatomical structures.