Archive image from page 219 of Cytology, with special reference to. Cytology, with special reference to the metazoan nucleus cytologywithspec00agar_0 Year: 1920 204 CYTOLOGY CHAP. two different phases of the life cycle of Coccidiam schubergi (Schaudinn, 1900). In the schizont (the asexual cycle), before nuclear division the chromatin granules become massed together in little clumps and irregular threads, in which, however, no definite longitudinal splitting can be made out, and they do not get collected into an equatorial plate. They sort themselves out in some way or other into two groups w
Archive image from page 219 of Cytology, with special reference to. Cytology, with special reference to the metazoan nucleus cytologywithspec00agar_0 Year: 1920 204 CYTOLOGY CHAP. two different phases of the life cycle of Coccidiam schubergi (Schaudinn, 1900). In the schizont (the asexual cycle), before nuclear division the chromatin granules become massed together in little clumps and irregular threads, in which, however, no definite longitudinal splitting can be made out, and they do not get collected into an equatorial plate. They sort themselves out in some way or other into two groups which appear to be pushed apart by the elongation of the karyosome, which contains, or takes the place of, the centrosome and achromatic figure. The nuclear divisions in the oocyst of the same species, which cover Fig. 84. Nuclear division in the asexual cycle of Coccidium schubergi. (After Schaudinn, , 1900.) A-E, the schizont; F-L, the oocyst. the first few divisions of the zygote nucleus after syngamy, are instructive as showing how nuclei which appear to divide in the most purely amitotic fashion may have undergone a previous reorganization which is presum- ably connected with the accurate partition of differentiated chromatin elements between the daughter nuclei (Fig. 84, F-L). There is a prophase closely resembling that of a Metazoan mitosis resulting finally in the formation of a relatively very thick and short spireme. This, however, breaks up into irregular fragments which become united to form a reticular nucleus again, and in this condition the nucleus divides. Although, therefore, the actual division appears to be amitotic it is difficult to avoid the conclusion that the previous arrangement of
Size: 1686px × 1186px
Photo credit: © Bookive / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: 1900, 1920, agar_w_e_wilfred_eade_1882_1951, americana, archive, blc, book, bookauthor, bookcentury, bookcollection, bookcontributor, bookdecade, bookpublisher, booksubject, bookyear, cells, drawing, historical, history, illustration, image, london_macmillan_and_co_limited, page, picture, print, reference, vintage, wellesley_college_library
