protostomes vs deuterostomes

Embryonic development of animals always begins with the union between a sperm and an egg. As development proceeds, a gastrula is formed and this gastrula makes a BLASTOPORE, or the First Hole. What happens to this hole? Find out in this video as you discover the difference between the protostomes and deuterostomes! Protostomes are a category of animal which includes worms, arthropods, and mollusks. Deuterostomes are a category that includes vertebrates and echinoderms.
- Susan Chung, science educator
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