GLAND CELLS IN HYDRA
b'The proliferative capacity of gland cells in Hydra attenuata was investigated. The results\\nindicate that both gland cell proliferation and interstitial cell differentiation to gland cells\\ncontribute to the maintenance of the whole population. On the basis of [3H]thymidine incorporation\\nand nuclear DNA measurements, gland cells consist of at least three different\\npopulations. One population consists of rapidly proliferating cells with a cell cycle of about 72 h.\\nThese cells are distributed throughout the body column. In the lower gastric region there is a\\npopulation of non-cycling cells in G2 while in the upper gastric region there is a population of noncycling\\ncells in G1. About half the G1 population becomes a new antigen, SEC 1, which is typical of\\nmucus cells.'