Blastula Formation and Embryonic Development

Flashcards containing key vocabulary and definitions related to blastula formation and embryonic development.

Blastula

A hollow sphere of cells formed during the early stages of embryonic development after cleavage.

Differentiation

The process by which cells become specialized in structure and function.

Polarity

The spatial differences in the shape, structure, and function of cells in an embryo.

Blastocoel

The fluid-filled cavity inside the blastula.

Tight junction

A type of connection between cells that prevents the passage of molecules and ions through the space between cells.

Epiblast

The outer layer of cells in the blastula that contributes to the formation of the ectoderm, mesoderm, and endoderm.

Hypoblast

The layer of cells in the blastula that forms the yolk sac and contributes to the formation of the endoderm.

Area pellucida

The clear, central area of the blastodisc in the chick blastula that becomes the embryo.

Area opaca

The opaque, peripheral area of the blastodisc that surrounds the area pellucida in the chick blastula.

Koller's sickle

A region in the chick blastula that serves as a signaling center for the development of the primitive streak.