. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. MITOGENETIC RAYS 119 During most of the period of the experiments the growth of the yeast is logarithmic. Should there be any acceleration of the multipli- cation of the yeast due to stimulation by mitogenetic radiation, it should show not only as an increase in the rate of growth but also as an in- creased yield in the quartz tubes over that obtained in the glass tubes. A slight acceleration, possibly less than would be noticed in the per- centages of budding, would be distinctly noticeable by the end of the period of growt
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. MITOGENETIC RAYS 119 During most of the period of the experiments the growth of the yeast is logarithmic. Should there be any acceleration of the multipli- cation of the yeast due to stimulation by mitogenetic radiation, it should show not only as an increase in the rate of growth but also as an in- creased yield in the quartz tubes over that obtained in the glass tubes. A slight acceleration, possibly less than would be noticed in the per- centages of budding, would be distinctly noticeable by the end of the period of growth. To test this the ratios of the number of cells in the quartz tubes to the number in the glass tubes at the end of each series were calculated. For the control which was shielded from the bacteria, the average of the ratios was showing that there were slightly more. FIGURE 2 FIG. 2. Arrangement for exposing tubes to radiation from onion roots. When in use, the beaker was partly filled with water to prevent drying of the onion roots. cells present in the glass than in the quartz tubes. The average of the same ratios for the tubes suspended in the bacterial culture was Since twice as many counts were averaged than with the special control, more of the variation is cancelled, which accounts for the index being nearer unity. The maximum yield is less in the quartz tubes than in the glass tubes, which again fails to indicate any stimulation of budding attributable to a mitogenetic radiation. When the logarithm of the number of cells is plotted against time, the slope of the resulting curve is the relative rate of multiplication of the cells. This graph is linear during all of these experiments except the last observation of five cultures, because the seeding was from ac-. 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
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
