. The cell in development and inheritance. Cells. CHEMICAL RELATIOXS OF NUCLEUS AND CYTOPLASM 339 1 /Lt in diameter. At the height of their development they are almost eight times their original length and twenty times their original diameter. In the final period they are but 2 /a in length and i /a in di- ameter. These measurements show a change of volume so enormous, even after making due allowance for the loose structure of the large chromosomes, that it cannot be accounted for by mere swelling or shrinkage. The chromosomes evidently absorb a large amount of a: •fc^^"^ 5.^. Fig. 157. -
. The cell in development and inheritance. Cells. CHEMICAL RELATIOXS OF NUCLEUS AND CYTOPLASM 339 1 /Lt in diameter. At the height of their development they are almost eight times their original length and twenty times their original diameter. In the final period they are but 2 /a in length and i /a in di- ameter. These measurements show a change of volume so enormous, even after making due allowance for the loose structure of the large chromosomes, that it cannot be accounted for by mere swelling or shrinkage. The chromosomes evidently absorb a large amount of a: •fc^^"^ 5.^. Fig. 157. - Chromosomes of the germinal vesicle in the shark Fristiurus, at different periods, drawn to the same scale. [Ruckekt.] A At the period of maximal size and minimal staining-capacity (egg 3 mm. in diameter) B. Later period (egg 13 mm. in diameter). C. At the close of ovarian life, of mmimal size and maximal staining-power. matter, combine with it to form a substance of diminished staining- capacity, and finally give off matter, leaving an intensely staining behind. As Riickert points out, the great increase of sur- face in the chromosomes is adapted to facilitate an exchange of mate- rial between the chromatin and the surrounding substance; and he concludes that the coincidence between the growth of the chromo- somes and that of the egg points to an intimate connection between the nuclear activity and the formative energy of the 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 Wilson, Edmund B. (Edmund Beecher), 1856-1939. New York, Macmillan
Size: 1790px × 1395px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectcells, bookyear1911
