In long bone development, a thin layer called periosteum covers early bone formation.

At four weeks, _______________________ carries poorly oxygenated blood from the umbilical vesicle to the tubular heart.

Select the correct answer for the indicated identification  

What type of urogenital anomaly is indicated in the image?

Type I alveolar epithelial cells (type I pneumocytes) are responsible for gas exchange and develop from endoderm.

The amniotic cavity appears on the 8th day as a slit-like space between the trophoblast and the

What gut tube anomaly is indicated in the image?

In heart development, the bulbus cordis forms the outflow tracts of the ventricles.

What type of kidney anomaly is represented in the image?

During what stage of lung development does surfactant begin being produced?