. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FORM REGULATION IN ZOOTHAMN1UM ALTERNANS 143 (1929) observed that a local injury to one of the main branches affected the zooids distal to the region of injury, inducing many of the micro- zooids to metamorphose into microgamonts ("microconjugants"). Similar effects on the whole colony were induced by unfavorable environmental conditions, inanition or lack of oxygen. He did not observe a regulatory response subsequent to the injury. Regulation after Conjugation.—From the following fragmentary account of the gr
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. FORM REGULATION IN ZOOTHAMN1UM ALTERNANS 143 (1929) observed that a local injury to one of the main branches affected the zooids distal to the region of injury, inducing many of the micro- zooids to metamorphose into microgamonts ("microconjugants"). Similar effects on the whole colony were induced by unfavorable environmental conditions, inanition or lack of oxygen. He did not observe a regulatory response subsequent to the injury. Regulation after Conjugation.—From the following fragmentary account of the growth activity manifest in conjugating colonies it is at once clear that this aspect of development alone constitutes a lengthy research problem. Only ten of the colonies whose lineage was being followed happened to conjugate so that a detailed analysis. FIG. 7. A colony several days after the onset of conjugation at the level of branch N. The ex-conjugant divided into a cluster of large zooids, one of which differentiated into a new whose further development prolonged the main axis. The exact lineage of these cells is not known. X 250. of the process is not immediately available. Much of that which follows is based upon conjugants observed among the adventitious growths on the culture slides whose histories are but imperfectly known. Conjugation is introduced here because it affords one clue to qualitatively different physiological relations between the apical zooid, the conjugant in this case, and a large area of the subordinate regions of the colony. So far the results obtained from regulation experiments bespeak a regular functional correlation between the single cell in the apical position and the zooids in sub-adjacent regions, such that the latter. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
