Germ Layers During Embryonic and Fetal Development

Key early structures of the mesoderm are the ________________ and _______________.

Somites Notochord

During the fetal development stage, the ectoderm forms which structures?

Structures of the nervous system (brain, spinal cord, eyes...) and the skin's epidermis.

During the fetal development stage, the mesoderm forms which structures?

All other tissues that the endoderm and ectoderm do not, such as bone, skeletal and smooth muscle, circulatory system, gonads, and kidneys...

During the embryonic stage, this germ layer resides on the upper surface.

Ectoderm

During the embryonic stage, this germ layer resides on the bottom surface.

Endoderm

During the embryonic stage, this germ layer migrates between the other two layers.

Mesoderm.

Name a distinctive feature of the ectoderm, during the embryonic stage.

Primitive streak

During the fetal development stage, the endoderm forms which structures?

The epithelial linings fo the digestive, respiratory, urinary and genital tracts (your various tubes).