Early Embryonic Development

Vocabulary flashcards covering key terms related to early embryonic development.

Trophoblast

The outer layer of cells that will later implant into the uterine wall.

Embryoblast

The inner ball of cells within the blastocyst, which will eventually develop into the embryo.

Embryonic Disc

The structure formed when the ball of cells takes up fluid, resulting in two distinct layers: the epiblast and the hypoblast.

Epiblast

The blue layer of cells in the bilaminar disc.

Hypoblast

The yellow layer of cells in the bilaminar disc.

Primary Germ Layers

The three initial cell layers (ectoderm, mesoderm, and endoderm) that develop in the early embryo and from which all tissues and organs will form.

Endoderm

The innermost germ layer; forms the lining of the digestive and respiratory tracts.

Mesoderm

The middle germ layer; forms muscles, bones, and other connective tissues.

Ectoderm

The outermost germ layer; forms the epidermis, brain, and spinal cord.