Embryonic Development and Body Cavities

These flashcards cover important vocabulary and concepts from Chapters 1 to 6 concerning embryonic development, body cavities, and their significance in biological classification.

Blastopore

The opening of the embryo during the gastrulation phase that allows the movement of cells into the inside of the hollow ball of cells.

Arcanteron

The structure that forms the gut during embryonic development after the blastopore stage.

Coelom

A body cavity that is not the digestive tract, formed within the mesoderm in true coelomates.

Pseudo coelomates

Animals that possess a body cavity, but it's formed differently than in true coelomates, typically with boundaries made from endoderm and mesoderm.

Cleavage

The process of cell division that occurs after fertilization, where the single cell divides to form a multicellular structure while maintaining the same overall size.

Embryonic development

The series of events from fertilization to the formation of tissue layers and structures in an embryo.

Protostome development

A mode of embryonic development where the blastopore becomes the mouth and the mesoderm forms near the blastopore.

Deuterostome development

A mode of embryonic development where the blastopore becomes the anus, and the mesoderm forms on the opposite end from the blastopore.

Indeterminate cell fate

A characteristic of deuterostomes where the fate of individual cells has not been predetermined by the early cell divisions.

Determinant cell fate

A characteristic of protostomes where the fate of cells is determined at the eight-cell stage.

Phylogenetic signal

A trait that helps define a group of organisms, indicating a common ancestry, such as bilateral symmetry or the presence of three tissue layers.

Hox genes

Genes that are crucial for anterior-posterior patterning in animals and are associated with bilateral symmetry and three tissue layers.