coelomate
Quick Summary
A coelomate is an animal with a true coelom, which is a body cavity located between the digestive tract and the body wall. This cavity is entirely lined by mesoderm, the middle of the three primary germ layers. The presence of a coelom allows for greater complexity and size in animals, as it suspends the internal organs and facilitates movement.123
Coelomates are broadly divided into two groups based on their embryonic development: protostomes and deuterostomes. In protostomes, the coelom typically forms from a splitting of the mesodermal mass (schizocoelous development), and the blastopore (the first opening in the embryo) becomes the mouth. Deuterostomes, on the other hand, usually form their coelom through outpouching of the embryonic gut (enterocoelous development), and the blastopore becomes the anus.2143
Ask Britannica AI about this topic
Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.
