3 Streaming submandibular gland

This  my third presentation which summarizes the current knowledge of the proliferation kinetics of cells in the body..
The first was Streaming Epidermis, a prototype of stratified epithelia.
The second  was Streaming Intestinal lining, a prototype of one cell layered  epithelia.

Epithelia are assembled in  epithelial proliferative units (EPU). The submandibular gland is assembled in similar units, the Acinar Proliferative Unit (APU)

1. EPU is monoclonal
2. EPU is oriented from stem cell and outward
3. Cells stream outward (to their graveyard)
4. As cells stream they differentiate.
5. Cells do not stream inward, they do not de-differentiate.
Acinus proliferative unit (APC) is equal to the terminal duct lobular unit (TDLU)
Both are EPUs