20
0
40h
30h
20^
240h
I60K
80h
16
8
12
Hours after division
20
24
FIG. 3. Total dry mass, u.v. absorption and Feulgen-stain measurements on HeLa tumourstrain nuclei, plotted against the cell ages (since mitosis) on a time-lapse film. In the uppermost diagram the individual measurements have been averaged at intervals throughout
interphase and the results are plotted together; the numbers at the top of the figure indicate
the number of cells representing each point, x
x, Feulgen D N A curve; 0
-
0,
dry mass curve; + , u.v. absorption (total nucleic acid) points. The mean intermitotic time of
the culture was of the order of 21 h: the one cell at 22 h which is in a longer synthetic cycle is
not included in the average measurements above. All the measurements are replotted in Fig. 5.
Nuclear nucleic acid
2
Nuclear dry mass xl0~
l2
g
xlO
H2
g
Feulgen stain Average dry mass x 10
0
40h
30h
20^
240h
I60K
80h
16
8
12
Hours after division
20
24
FIG. 3. Total dry mass, u.v. absorption and Feulgen-stain measurements on HeLa tumourstrain nuclei, plotted against the cell ages (since mitosis) on a time-lapse film. In the uppermost diagram the individual measurements have been averaged at intervals throughout
interphase and the results are plotted together; the numbers at the top of the figure indicate
the number of cells representing each point, x
x, Feulgen D N A curve; 0
-
0,
dry mass curve; + , u.v. absorption (total nucleic acid) points. The mean intermitotic time of
the culture was of the order of 21 h: the one cell at 22 h which is in a longer synthetic cycle is
not included in the average measurements above. All the measurements are replotted in Fig. 5.
Nuclear nucleic acid
2
Nuclear dry mass xl0~
l2
g
xlO
H2
g
Feulgen stain Average dry mass x 10