During embryonic development, if the anus develops before the mouth, the organism is a protostome deuterostome invertebrate vertebrate

Answer : The correct for the blank is-

deuterostome.

Deuterostomes are the organisms in which anus develops first from the first opening of the embryonic development, which is blastopore.

In other words, blastopore develops into anus first (unlike protostomes where mouth is develped from the blastopore) in case of deuterostome.

Example of Deuterostomes - Chordates and Echinoderms.

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