Tag Archive | "Streak"

Primitive Streak

Friday, September 19, 2008

0 Comments

At one circular area near the margin of the disc the cubical cells of the endoderm become columnar. This area is called “PROCHARDAL PLATE.” The appearance of the prochardal plate determines the central axis of the embryo and also enables us to distinguish its head and tail ends.

Continue reading...
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