. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 158 KATSUMA DAN AND JEAN CLARK DAN catch slight bending of the spindle even in the so-called "regularly dividing" sea- urchin eggs, in batches in which the spindle lies more or less off the geometrical center of the cell (sec Fry, 1937; Figs. 1-5). Another fact of special importance is that some of the investigations cited above include figures of spindle bending which occur well before a cleavage furrow is formed, thus definitely eliminating the pos- sibility that the spindle is passively bent inward by the advanc
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 158 KATSUMA DAN AND JEAN CLARK DAN catch slight bending of the spindle even in the so-called "regularly dividing" sea- urchin eggs, in batches in which the spindle lies more or less off the geometrical center of the cell (sec Fry, 1937; Figs. 1-5). Another fact of special importance is that some of the investigations cited above include figures of spindle bending which occur well before a cleavage furrow is formed, thus definitely eliminating the pos- sibility that the spindle is passively bent inward by the advancing cleavage furrow. ARTIFICIAL INDUCTION OF SPINDLE BENDING The foregoing analysis furnishes evidence that the cause of spindle bending is an unbalanced condition of the mechanical strains between the animal and vegetal sides of the spindle. If such is the case, by experimentally causing a similar un- balanced condition of force, it should be possible to induce spindle bending in a ma- terial in which it is not seen normally. This is achieved by the use of ether. The eggs of any kind of echinoid which normally divide in a symmetrical fashion can be used. The eggs are fertilized and a short time before the first cleavage is due, the surrounding sea-water is changed to an ether-sea-water mixture ( by volume).. 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 Marine Biological Laboratory (Woods Hole, Mass. ); Marine Biological Laboratory (Woods Hole, Mass. ). Annual report 1907/08-1952; Lillie, Frank Rattray, 1870-1947; Moore, Carl Richard, 1892-; Redfield, Alfred Clarence, 1890-1983. Woods Hole, Mass. : Marine Biological Laboratory
Size: 1500px × 1665px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
