Origins & Functions of Organs of the Ventral Body Cavity

These flashcards cover key vocabulary related to the lecture on the origins and functions of the coelomic cavity and organ development in vertebrates and invertebrates.

Coelomic Cavity

The body cavity located between the alimentary canal and the body wall, lined by mesoderm.

Ectoderm

The outermost germ layer that gives rise to the skin and nervous system.

Mesoderm

The middle germ layer that develops into muscle, bone, and blood.

Endoderm

The innermost germ layer that develops into the gut lining and associated organs.

Protostome

An organism whose embryonic development first forms the mouth from the blastopore.

Deuterostome

An organism whose embryonic development first forms the anus from the blastopore.

Schizocoely

The process of coelom formation by splitting mesoderm in protostomes.

Enterocoely

The process of coelom formation by the outpocketing of the mesoderm in deuterostomes.

Acoelomate

An organism with no true coelomic cavity, body filled with mesenchyme; includes flatworms.

Pseudocoelomate

An organism with a fluid-filled body cavity (pseudocoel) that is not entirely lined with mesoderm; includes nematodes.

Coelomate

An organism with a true coelom that is fully lined with mesoderm, such as annelids and vertebrates.

Gastrulation

The process in embryonic development that reorganizes a single-layered blastula into a multi-layered gastrula.