Whitman the entire nephridial system (in the leech Clepsine) is formed by the differentiation of a continuous epiblastic band on each side. [Please select]
0
Gastrula: that embryonic stage resembling a sac, with an outer layer of epiblastic cells and an inner layer of hypoblastic cells. [Please select]
Do you have a better example in your mind? Please submit your sentence!